chem e 20050513 final - hkedcity · “metals and non-metals”, “periodicity”, “mole and...

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Contents

Preamble

Chapter 1 Introduction Rationale 1 Curriculum Aims 2 Chapter 2 Curriculum Framework Structure of the Curriculum 3 Learning Targets 6 Compulsory Part 8 Elective Part 69 Investigative Study 85 Chapter 3 Curriculum Planning Interface with the Junior Secondary Science Curriculum 88 Progression of Studies 90 Suggested Learning and Teaching Sequences 93 Chapter 4 Learning and Teaching Designing Learning Activities 97 Information Technology (IT) for Interactive Learning 100 Providing Life-wide Learning Opportunities 100 Chapter 5 Assessment Aims of Assessment 101 Internal Assessment 101 Public Assessment 101 Chapter 6 Effective Use of Learning and Teaching Resources 104

Chapter 7 Supporting Measures 105

References 106

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Preamble

The Curriculum Development Council (CDC)-Hong Kong Examinations and Assessment Authority (HKEAA) Committees (Senior Secondary) of various subjects have been set up jointly by the CDC and the HKEAA Council to develop the Curriculum and Assessment Guides (C&A Guides) for the new 3-year senior secondary academic structure in Hong Kong. During the first stage of consultation on the new academic structure between October 2004 and January 2005, the document Reforming the Academic Structure for Senior Secondary Education and Higher Education - Actions for Investing in the Future (Education and Manpower Bureau, 2004) was published to seek stakeholders’ views on the design blueprint of the structure, the timetable for implementation and financial arrangements. An accompanying document, Proposed Core and Elective Subject Frameworks for the New Senior Secondary Curriculum, was also produced to solicit views and feedback from schools on the initial curriculum and assessment design of individual subjects to inform the development of the C&A Guides.

The report New Academic Structure for Senior Secondary Education and Higher Education – Action Plan for Investing in the Future of Hong Kong (Education and Manpower Bureau, 2005), an outcome of the first stage of consultation, has just been published to chart the way forward for implementing the new academic structure and to set further directions for the second stage of consultation on curriculum and assessment as part of the interactive and multiple-stage process of developing the C&A Guides. In addition, taking into consideration the feedback collected through various means including the returned questionnaires from key learning area coordinators/panel heads during the first stage of consultation, the curriculum and assessment frameworks of subjects have been revised and elaborated. We would like to solicit further views on the frameworks from stakeholders, in particular the school sector.

To understand the position of each subject in the new academic structure, readers are encouraged to refer to the report. Comments and suggestions on the Proposed New Senior Secondary Chemistry Curriculum and Assessment Framework are welcome and could be sent to:

Chief Curriculum Development Officer (Science Education) 401, 4/F., Tin Kwong Road, Kowloon Fax: 2194 0670 E-mail: [email protected]

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Chapter 1 Introduction

1.1 Chemistry is one of the elective subjects offered in the Key Learning Area (KLA) of Science Education1. The new Chemistry Curriculum serves as a continuation of the Science (S1-3) Curriculum and builds on the strength of the current Chemistry curricula. It will provide a range of balanced learning experiences through which students can develop the necessary scientific knowledge and understanding, skills and processes, and values and attitudes embedded in the strand “The Material World” of science education and other related strands for personal development, and for contributing towards a scientific and technological world. The curriculum will prepare students for entering tertiary courses, vocation-related courses or the workforce in various fields related to chemistry. Rationale 1.2 The emergence of a highly competitive and integrated economy, rapid scientific and technological innovations, and a growing knowledge base will continue to have a profound impact on our lives. In order to meet the challenges posed by these changes, Chemistry, like other science electives, will provide a platform for developing scientific literacy and for building up essential scientific knowledge and skills for life-long learning in science and technology. 1.3 Chemistry deals with the composition, structures, and properties of matter; and the interactions between different types of matter, and the relationship between matter and energy. Through the learning of chemistry, it is possible to acquire relevant conceptual and procedural knowledge. In addition, a study of chemistry also helps to develop understanding and appreciation of developments in engineering, medicine and other related scientific and technological fields. Furthermore, learning about the contributions, issues and problems related to innovations in chemistry will help students develop a holistic view of the relationships between science, technology, society and the environment.

1 There will be four elective subjects offered in the Key Learning Area of Science Education, namely Biology, Chemistry, Physics and Science. The design of the subject Science will include two modes – integrated and combined. This curriculum will contribute towards the chemistry part of the combined mode – Science (Chemistry, Physics) and Science (Biology, Chemistry).

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1.4 The curriculum attempts to make the study of chemistry exciting and relevant. It is suggested to introduce the learning of chemistry in real life contexts. The adoption of diverse contexts, learning and teaching strategies, and assessment practices is intended to appeal to students of all abilities and aspirations, and to stimulate interest and motivation for learning. Together with other learning experiences, students are expected to be able to apply their knowledge of chemistry, to appreciate the relationship between chemistry and other disciplines, to be aware of the science-technology-society-environment (STSE) connections of contemporary issues, and to become responsible citizens.

Curriculum Aims 1.5 The overarching aim of the Senior Secondary Chemistry Curriculum is to provide chemistry-related learning experiences for students to develop scientific literacy, so that they can participate actively in our rapidly changing knowledge-based society, prepare for further studies or careers in fields related to chemistry, and become life-long learners in science and technology.

The broad aims of the curriculum are to enable students to:

• develop interest and maintain a sense of wonder and curiosity in chemistry;

• construct and apply knowledge of chemistry, and appreciate the relationship between chemistry and other disciplines;

• appreciate and understand the evolutionary nature of science;

• develop skills for making scientific inquiries;

• develop the ability to think scientifically, critically and creatively, and solve problems individually and collaboratively in chemistry-related contexts;

• communicate ideas and views of science-related issues using the language of chemistry;

• make informed decisions and judgments on chemistry-related issues;

• develop open-mindedness, objectivity and pro-activeness;

• show appropriate awareness of working safely;

• be aware of the social, ethical, economic, environmental and technological implications of chemistry, and develop an attitude of responsible citizenship.

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Chapter 2 Curriculum Framework

Structure of the Curriculum 2.1 The curriculum will consist of compulsory and elective parts. The compulsory part will cover a range of content that enables students to develop an understanding of fundamental chemistry principles and concepts, and the scientific process skills. It is suggested to include topics such as “atomic structure”, “bonding, structures and properties”, “metals and non-metals”, “periodicity”, “mole and stoichiometry”, “acids and bases”, “electrochemistry”, “chemistry of carbon compounds”, “chemical energetics”, “chemical kinetics” and “chemical equilibrium”. Please refer to topics I to XII for details. 2.2 To cater for the diverse interests, abilities and needs of students, an elective part will be included in the curriculum. The elective part aims to provide an in-depth treatment of some of the compulsory topics, or an extension of certain areas of study. In addition, “green chemistry” will also be introduced in this part of study. Some suggested choices are: “industrial chemistry”, “materials chemistry” and “analytical chemistry”. Please refer to topics XIII to XV for details. 2.3 To facilitate the integration of knowledge and skills acquired, students are required to conduct an investigative study relevant to the curriculum. A proportion of total lesson time will be allocated to this study. Please refer to Topic XVI “Investigative Study in Chemistry” for details. 2.4 The time allocations for the compulsory and elective parts are listed below.

Compulsory Part (Total 200 hours) Suggested lesson

time (hrs)

I. Planet earth* 8

II. Microscopic world I* 22

III. Metals* 22

IV. Acids and bases* 27

V. Fossil fuels and carbon compounds* 24

VI. Microscopic world II* 11

VII. Redox reactions, chemical cells and electrolysis* 26

* These topics are proposed to be included in the chemistry part of Science (Chemistry, Physics) and Science (Biology, Chemistry).

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Compulsory Part (Total 200 hours) Suggested lesson

time (hrs)

VIII. Chemical reactions and energy* 9

IX. Rate of reaction 9

X. Chemical equilibrium 10

XI. Chemistry of carbon compounds 22

XII. Patterns in the chemical world 10

Subtotal: 200

Elective Part (Total 52 hours, select any 2 out of 3)

XIII. Industrial chemistry 26

XIV. Materials chemistry 26

XV. Analytical chemistry 26

Subtotal: 52

Investigative Study (18 hours)

XVI. Investigative study in chemistry 18

Total lesson time: 270 2.5 The content of the curriculum is organised into 15 topics and an investigative study. However, the concepts and principles of chemistry are inter-related and should not be confined by any artificial boundaries of topics. The order of presentation of the topics in this chapter can be regarded as a possible teaching sequence. Teachers should adopt sequences that best suit their chosen teaching approaches. For instance, some parts of a certain topic may be covered in advance if they fit in naturally with a chosen context. Please refer to Suggested Learning and Teaching Sequences in Chapter 3. 2.6 There are five major parts in each of the topics I to XV: Overview, Learning Objectives and Outcomes, Suggested Learning and Teaching Activities, Values and Attitudes, and STSE connections.

Overview – outlines the main theme of the topic. The major concepts and important chemistry principles to be acquired will be highlighted. The foci of each

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topic will be briefly described. The interconnections between subtopics will also be outlined.

Learning Objectives and Outcomes – lists out the learning objectives and outcomes acquired by students in the knowledge content domain of the curriculum. It provides a broad framework upon which learning and teaching activities can be developed. Suggested Learning and Teaching Activities – gives suggestions to some of the different skills that are expected to be acquired in the topic. Some important processes associated with the topic are also briefly described. Since most of the generic skills can be acquired through any of the topics, there is no attempt to give directive recommendation on the activities that should be performed. Students need to acquire a much broader variety of skills than what are mentioned in the topics. Teachers should use their professional judgement to arrange practical and learning activities to develop the skills of students as listed in the Learning Objectives of the Curriculum Framework. It should be done through appropriate integrations with the knowledge content, taking into consideration students’ abilities and interests as well as school contexts. Values and Attitudes – suggests some desirable values and attitudes that can be related to the study in the topic. Students are expected to develop such intrinsically worthwhile values and positive attitudes in the course of the study of chemistry. Through discussions and debates, students are encouraged to form their value judgement and develop good habits for the benefit of themselves and the society. STSE connections – suggests some issue-based learning activities or subjects related to the topic. Students should be encouraged to develop an awareness of and comprehend issues associated with the interconnections of science, technology, society and the environment. Through discussion, debate, information search and project work, students can develop communication skills, information handling, critical thinking and making informed judgement. Teachers are free to select other current, relevant topics and issues in the public agenda for meaningful learning activities.

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Learning Targets 2.7 The learning targets of this curriculum are categorised into three domains: knowledge and understanding, skills and processes, and values and attitudes. Through the learning embodied in the Chemistry Curriculum, students will acquire relevant learning targets in various chemistry-related contexts.

Knowledge and Understanding

Students are expected to:

understand phenomena, facts and patterns, principles, concepts, laws and theories in chemistry;

learn chemical vocabulary, terminology and conventions;

appreciate applications of chemistry in society and in everyday life;

develop an understanding of methods used in scientific investigation.

Skills and Processes


develop scientific thinking and problem-solving skills;

acquire an analytical mind to critically evaluate chemistry-related issues;

communicate scientific ideas and values in meaningful and creative ways with appropriate use of symbols, formulae, equations and conventions;

acquire practical skills such as manipulate apparatus and equipment, handle chemicals, carry out given procedures, analyse and present data, draw conclusions and evaluate experimental procedures;

plan and conduct scientific investigations individually and collaboratively with appropriate instruments and methods, assess possible risks, collect quantitative and qualitative data with accuracy, analyse and present data, draw conclusions, and evaluate evidence and procedures;

develop study skills to improve the effectiveness and efficiency of learning; and develop abilities and habits that are essential to life-long learning.

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Values and Attitudes


develop curiosity and interest in making scientific investigation; develop personal integrity through objective observation and honest

recording of experimental data; and be committed to safe practices when handling chemicals;

be willing to communicate and make decisions on issues related to chemistry and demonstrate an open-minded attitude towards the views of others;

be aware that chemistry is a developing science and has its limitations; appreciate the interrelationship of chemistry with other disciplines in

providing social and cultural values; appreciate the importance of working safely in laboratory; be aware of the impact of chemistry on social, economic, industrial,

environmental and technological contexts.

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Compulsory Part (Total 200 hours)

Topic I Planet Earth (8 hours)

Overview The natural world is made up of chemicals. The earth’s crust, the sea and the atmosphere are major sources of chemicals. The purpose of this topic is to provide opportunity for students to appreciate that as we are living in a world of chemicals, chemistry is socially relevant and an important area of learning. Another purpose of this topic is to allow students to recognise that the study of chemistry includes the investigation of possible methods to isolate useful materials from the sources mentioned earlier, and the analysis of these materials using various tests. Furthermore, students who have completed this topic are expected to have a better understanding of scientific investigation and chemistry concepts learnt in the junior science curriculum. Students should know the terms “element”, “compound” and “mixture”, “physical change” and “chemical change”, “physical property” and “chemical property”, “solvent”, “solute” and “saturated solution”. They should also be able to use word equations to represent chemical changes, and to suggest appropriate methods for the separation of mixtures and tests for some chemical species.

Learning Objectives and Outcomes

Students should learn Students should be able to

a. The atmosphere composition of air separation of oxygen and nitrogen

from liquid air by fractional distillation

test for oxygen

apply skills for searching information from

various sources and present findings orally describe the processes involved in fractional

distillation of liquid air, and understand the concepts and procedures involved

carry out a test for oxygen

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b. The Ocean

composition of sea water extraction of common salt and

isolation of pure water from sea water

tests to show the presence of sodium and chloride in a sample of common salt

test for the presence of water in a sample

electrolysis of sea water and uses of the products

describe various kinds of minerals in the sea demonstrate how to extract common salt and

isolate pure water from sea water describe the processes involved in evaporation,

distillation, crystallisation and filtration as different kinds of physical separation methods and understand the concepts and procedures involved

evaluate the appropriateness of using evaporation, distillation, crystallisation and filtration for different physical separation situations

demonstrate how to carry out flame test, test for chloride and test for water

c. Rocks and minerals

rocks as a source of minerals isolation of useful materials from

minerals as exemplified by extraction of metals from their ores

limestone, chalk and marble as different forms of calcium carbonate

erosion processes as exemplified by the action of heat, water and acids on calcium carbonate

thermal decomposition of calcium carbonate and test for carbon dioxide

tests to show the presence of calcium and carbonate in a sample of limestone/chalk/marble

describe the methods for extraction of metals from

their ores and acquire some related experimental skills

describe different forms of calcium carbonate in nature

understand that chemicals may change by the action of heat, water and acids

use word equations to describe chemical changes demonstrate how to carry out test for carbon

dioxide and calcium

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Suggested Learning and Teaching Activities Students are expected to develop the learning outcomes using a variety of learning experiences; some related examples are: searching for information on issues related to the atmosphere, such as the applications

of the products obtained from fractional distillation of liquid air, air pollutants. using an appropriate method to test for oxygen and carbon dioxide. performing experiments and evaluating methods on physical separation including

evaporation, distillation, crystallisation and filtration. using appropriate apparatus and techniques to carry out the flame test and test for

chloride. performing a test to show the presence of water in a given sample. problem-solving exercises on separating mixtures (e.g. a mixture of salt, sugar and sand,

a mixture of sand, water and oil). investigating the actions of heat, water and acids on calcium carbonate. designing and performing chemical tests for calcium carbonate. participating in decision-making exercises or discussion on issues related to

conservation of natural resources. describing chemical changes using word equations.


Students are expected to develop in particular, values and attitudes, as follows:

to value the need for the safe handling and disposing of chemicals.

to appreciate that the earth is the source of a variety of materials useful to human beings.

to show concern over the limited reserve of natural resources.

to show an interest in and curiosity about chemistry.

to appreciate the contribution of chemists in separation and identification of chemical species.

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STSE Connections

Students are encouraged to appreciate and to comprehend issues which reflect the interconnections of science, technology, society and the environment; some related examples are listed below:

Oxygen extracted from air can be used for medicinal purposes.

Methods involving chemical reactions are used to purify drinking water for travellers to districts without clean and safe water supply.

Desalination is an alternative means of providing fresh water to the people of Hong Kong SAR people than importing water from the GuangDong province.

Mining and extraction of chemicals from the earth should be regulated to conserve the environment.

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Topic II Microscopic World I (22 hours)

Overview The study of chemistry involves the linking of phenomena in the macroscopic world to the interaction of atoms, molecules and ions in the microscopic world. Through a study of the structures of atoms, molecules and ions, and the bonding in elements and compounds, students will acquire knowledge of some basic chemical principles in order to further illustrate the macroscopic level of chemistry, such as patterns of changes, observations in various chemical reactions, rates of reactions and chemical equilibria. Through this, students should be able to perform calculations related to chemical formulae, which are the basis of mole calculations to be learned in the latter topics. Furthermore, students should be able to appreciate the interrelation between bonding, structures and properties of substances by learning the properties of giant ionic and simple molecular substances. In addition, students will learn more about simple molecular substances such as the shapes and the non-octet structures of some covalent molecules. Through activities such as gathering and analysing information about atomic structure and the Periodic table, students should appreciate the impact of history about discoveries of atomic structure and development of the Periodic Table on modern chemistry. Students should also be able to appreciate that symbols and chemical formulae constitute part of the common language used by scientists to communicate chemical concepts.

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a. Atomic structure elements, atoms and symbols classification of elements into

metals, non-metals and metalloids electron, neutron and proton as

subatomic particles simple model of atom atomic number (Z) and mass

number (A) isotopes isotopic masses and relative

atomic masses based on 12C=12.00

electronic arrangement of atoms (up to Z=20)

stability of noble gases related to their electronic arrangements

state the relationship between element and atom use symbols in representing elements understand that elements can be classified as

metals or non-metals on the basis of their properties and be aware that some elements possess characteristics of both metals and non-metals

state and compare the relative charges and the relative masses of a proton, a neutron and an electron

describe the structure of an atom in terms of protons, neutrons and electrons

interpret and use symbols such as Na2311

deduce the numbers of protons, neutrons and electrons in atoms and ions with given atomic number and mass number

identify isotopes among elements with atomic symbols

perform calculations related to isotopic masses and relative atomic masses

understand and deduce the electronic arrangements of atoms

represent the electronic arrangements of atoms in terms of electron diagrams

relate the stability of noble gases to the octet rule

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b. The Periodic Table the position of the elements in the

Periodic Table related to their electronic arrangements

similarities in chemical properties among elements in Groups I, II, VII and 0

appreciate the Periodic Table as a systematic way

to arrange elements and understand this special arrangement

define group number and period number of an element in the Periodic Table

relate the position of an element in the Periodic Table to its electronic structure and vice versa

relate the electronic arrangements to the chemical properties of the Group I, II, VII and 0 elements

describe differences in reactivity of Group I, II and VII elements

predict chemical properties of unfamiliar elements in a group of the Periodic Table

c. Metallic bonding describe the simple model of metallic bond d. Structures and properties of metals describe the general properties of metals

relate the properties of metals to their giant metallic structures

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e. Ionic and covalent bond transfer of electrons in the

formation of ionic bond cations and anions electronic diagrams of simple

ionic compounds names and formulae of ionic

compounds ionic structure as illustrated by

sodium chloride sharing of electrons in the

formation of covalent bond single, double and triple bonds electronic diagrams of simple

covalent molecules names and formulae of covalent

compounds formula masses and relative

molecular masses

describe, using electronic diagrams, the formation

of ions and ionic bonds draw the electronic diagrams of cations and

anions predict the ions formed by atoms of metals and

non-metals by using information of the Periodic Table

identify polyatomic ions name some common cations and anions according

to the chemical formulae of ions name ionic compounds based on the component

ions describe the colour of some common ions in

aqueous solutions interpret chemical formulae of ionic compounds

in terms of the elements present and the ratios of their atoms

construct formulae of ionic compounds based on their names or component ions

describe the structure of an ionic crystal describe the formation of a covalent bond describe, using electronic diagrams, the formation

of single, double and triple covalent bonds describe the formation of dative covalent bond by

using electronic diagrams interpret chemical formula of covalent compounds

in terms of the elements present and the ratios of their atoms

write the names and formulae of covalent compounds based on their component atoms

communicate scientific ideas with appropriate use of chemical symbols and formulae

define and differentiate the terms: formula mass and relative molecular mass

perform calculations related to formula masses and relative molecular masses of compounds

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f. Structures and properties of giant ionic and simple molecular substances

describe giant ionic structures of substances such as sodium chloride and caesium chloride

state and explain the properties of ionic compounds in terms of their structures and bonding

describe simple molecular structures of substances such as CH4, NH3 and H2O

identify van der Waals’ forces in molecular substances

state and explain the properties of simple molecular substances in terms of their structures and bonding

g. Simple molecular substances with

non-octet structures recognise the existence of covalent molecules

with non-octet structures draw the electronic diagrams of some non-octet

molecules such as BF3, PCl5 and SF6 h. Shapes of simple molecules describe and draw three-dimensional diagrams to

represent shapes of the following molecules: CH4, NH3, H2O, BF3, PCl5 and SF6

Suggested Learning and Teaching Activities

Students are expected to develop the learning outcomes using a variety of learning experiences; some related examples are:

searching for and presenting information on the discoveries related to the structure of the atom.

searching for and presenting information on elements and the development of the Periodic Table.

performing calculations related to relative atomic masses, formula masses and relative molecular masses.

drawing electronic diagrams to represent atoms, ions and molecules. investigating chemical similarities of elements in the same group of the Periodic Table. predicting chemical properties of unfamiliar elements in a group of the Periodic Table. writing chemical formulae for ionic and covalent compounds.

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naming ionic and covalent compounds. investigating relationship of colour and composition of some gem stones. predicting colours of ions from a group of aqueous solution (e.g. predicting colour of K+,

Cr2O72− and Cl− from aqueous solutions of potassium chloride and potassium

dichromate). investigating the migration of ions, e.g. copper(II) dichromate, potassium permanganate,

towards oppositely charged electrodes. building models of ionic substances and covalent molecules. using computer programs to display three-dimensional images of ionic crystals and

simple molecular substances. investigating and comparing properties of ionic and simple molecular substances.



to appreciate that scientific evidence is the foundation for generalisations and explanations about matter.

to appreciate the usefulness of models and theories in helping to explain the structures and behaviours of matter.

to appreciate the perseverance of scientists in developing the Periodic Table and hence to envisage that scientific knowledge changes and accumulates over time.

to appreciate the restrictive nature of evidence when interpreting observed phenomena.

STSE Connections

Students are encouraged to appreciate and to comprehend issues which reflect the interconnections of science, technology, society and the environment; some related examples are:

Using universal convention of chemical symbols and formulae facilitates communication among people in different parts of the world.

Different substances have their own characteristic properties according to their chemical structures and therefore they are used differently in daily life.

The development of new materials to replace pure metals is needed in order to enhance the performance of some products, such as vehicles, aerocrafts, window frames and spectacles.

Common names of substances can be related to their systematic names (e.g. Table salt and sodium chloride; baking soda and sodium hydrogencarbonate).

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Topic III Metals (22 hours)

Overview Metals find a wide range of uses in our daily life, and as such the extraction of metals from their ores has been an important activity of human beings since prehistoric times. This topic provides opportunity for students to develop an understanding of how metals are extracted from their ores and how they react with other substances. Students are expected to establish a reactivity series of metals based on experimental evidence. The corrosion of metals poses a socioeconomic problem to human beings. It is therefore necessary to develop methods to preserve the limited reserve of metals. An investigation of factors leading to corrosion and methods to prevent metals from corroding is a valuable problem solving exercise and can help students develop a positive attitude towards the use of resources on our planet earth. A chemical equation is a concise and universally adopted way to represent a chemical reaction. Students should be able to transcribe word equations into chemical equations and appreciate that a chemical equation shows a quantitative relationship between reactants and products in a reaction. Students should also be able to do calculations involving the mole and chemical equations. The mole concepts acquired from this topic prepare students to perform further calculations involving concentration of solutions, molar volume of gases and equilibrium constant of reaction in other topics of the curriculum.

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a. Occurrence and extraction of metals occurrence of metals in nature in

free state and in combined forms obtaining metals by heating metal

oxides or by heating metal oxides with carbon

extraction of metals by electrolysis

relation of the discovery of metals with the ease of extraction of metals and the availability of raw materials

limited reserve of metals and their conservations

state the source of metals and their occurrence in

nature explain why extraction of metals is needed understand that the extraction of metals involves

reduction of their ores describe and explain the major methods of

extraction of metals from their ores relate the ease of obtaining metals from their ores

to the reactivity of the metals deduce the order of discovery of some metals

from their relative ease of extraction write word equations for the extraction of metals describe metal ores as a finite resource and hence

the need to recycle metals evaluate the recycling of metals using social,

economic and environmental perspectives

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b. Reactivity of metals reactions of some metals (sodium,

calcium, magnesium, zinc, iron, lead, copper, etc.) with oxygen/air, water, dilute hydrochloric acid and dilute sulphuric acid

metal reactivity series and the tendency of metal to form positive ion

displacement reactions and their interpretations based on the reactivity series

prediction of the occurrence of reactions involving metals using the reactivity series

relation between the extraction method for a metal and its position in the metal reactivity series

describe and compare the reactions of some

common metals with oxygen/air, water and dilute acids.

write the word equations for the reactions of metals with oxygen/air, water and dilute acids.

construct a metal reactivity series by reference to their reactions, if any, with oxygen/air, water and dilute acids

write balanced chemical equations to describe various reactions

use the state symbols (s), (l), (g) and (aq) in writing chemical equations

relate the reactivity of metal to the tendency of metal to form positive ion

describe and explain the displacement reactions involving various metals and metal compounds in aqueous solutions

deduce the order of reactivity of metals from given information

write balanced ionic equations predict the feasibility of metal reactions based on

the metal reactivity series relate the extraction method of a metal to its

position in the metal reactivity series

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c. Reacting masses quantitative relationship of the

reactants and the products in a reaction as revealed by a chemical equation

the mole, Avogadro’s constant and molar mass

percentage by mass of an element in a compound

empirical formulae and molecular formulae derived from experimental data

reacting masses from chemical equations

understand and use the quantitative information

provided by a balanced chemical equation perform calculations related to moles, Avogadro’s

constant and molar masses find the percentage by mass of an element in a

compound when given appropriate information determine empirical formulae and molecular

formulae from compositions by mass and molar masses

calculate and interrelate masses of reactants and products in a reaction from the relevant equation

solve problems involving percentage yield and limiting reagents.

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d. Corrosion of metals and their protection factors that influence the rusting

of iron methods used to prevent rusting socioeconomic implications of

rusting corrosion resistance of aluminium anodisation as a method to

enhance corrosion resistance of aluminium

state the nature of iron rust describe the essential conditions for the rusting of

iron describe and explain factors that influence the

speed of rusting of iron describe the observations when rust indicator is

used in the experiment that investigates rusting describe and explain the methods of rusting

prevention as exemplified by i. coating with paint, oil or plastic ii. galvanizing iii. tin-plating iv. electroplating v. sacrificial protection vi. alloying

aware of the socioeconomics impacts of rusting understand why aluminium is less reactive and

more corrosion resistant than expected describe how the corrosion resistance of

aluminium can be enhanced by anodisation



searching for and presenting information about the occurrence of metals and their uses in daily life.

analyse information to relate the chronology of the Bronze Age, the Iron Age and the modern era and possible future development.

designing and performing experiments to extract metals from metal oxides (e.g. silver oxide, copper(II) oxide, lead(II) oxide, iron(III) oxide).

deciding appropriate methods for the extraction of metals from their ores. transcribing word equations into chemical equations. performing experiments to investigate reactions of metals with oxygen / air, water and

dilute acids.

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constructing a metal reactivity series based on experimental evidence. performing experiments to investigate displacement reactions of metals with aqueous

metal ions. writing ionic equations. performing experiments to determine empirical formulae of magnesium oxide or

copper(II) oxide. performing calculations related to moles and reacting masses. designing and performing experiments to investigate factors that influence rusting. performing experiments to study methods that can be used to prevent rusting. deciding appropriate methods to prevent metal corrosion based on social, economic and

technological considerations. searching for and presenting information about the metal-recycling industry of Hong

Kong and the measures of conserving metal resources in the world. Values and Attitudes


to appreciate the contribution of science and technology in providing us with useful materials.

to appreciate the importance of making fair comparisons in scientific investigations.

to value the need for adopting safety measures when performing experiments involving potentially dangerous chemicals and violent reactions.

to show concern for the limited reserve of metals and realise the need for conserving and using these resources wisely.

to appreciate the importance of the mole concept in the study of quantitative chemistry.

to appreciate the contribution of chemistry in developing methods of rust prevention and hence benefiting the socioeconomics.

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STSE Connections


Although the steel industry has been one of the major profit-making industries in mainland China, there are many constraints for the growth of the industry, e.g. China has a shortage of raw materials.

New technologies are being implemented to increase the efficiency of the metal extraction process and at the same time to limit their impacts to the environment.

Conservation of metal resources should be promoted to arouse the concern of environmental protection.

New alloys are being developed to cope with different needs, e.g. new aluminium alloys for automotive and aerospace industries.

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Topic IV Acids and Bases (27 hours)

Overview Acids and bases/alkalis are involved in numerous chemical processes that occur around us, from industrial processes to biological ones, from reactions in the laboratory to those in our environment. Students have encountered acids and alkalis in their junior science courses. In this topic, they will further study the properties and reactions of acids and bases/alkalis, and the concept of molarity. Students should also be able to develop an awareness of the potential hazards associated with the handling of acids and alkalis. Moreover, students will learn instrumental methods of pH measurement, methods of salt preparation, and volumetric analysis involving acids and alkalis. Through these experimental practices students should be able to demonstrate essential experimental techniques, to analyse data and to interpret experimental results. On completion of this topic, students are expected to have acquired skills that are essential to conducting the investigative study required in the curriculum, as well as some basic knowledge for further study in Analytical Chemistry and carrying out more complicated quantitative analysis in chemistry.

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a. Introduction to acids and alkalis common acids and alkalis in daily

life and in the laboratory characteristics and chemical

reactions of acids as illustrated by dilute hydrochloric acid and dilute sulphuric acid

acidic properties and hydrogen ions (H+(aq))

role of water in exhibiting characteristic properties of acid

basicity of acid characteristics and chemical

reactions of alkalis as illustrated by sodium hydroxide and aqueous ammonia

alkaline properties and hydroxide

ions (OH−(aq)) corrosive nature of concentrated

acids and concentrated alkalis

identify the common acids found in household

items and in the laboratory describe the characteristics of acids and their

typical reactions write chemical and ionic equations for the

reactions of acids relate acidic properties to the presence of

hydrogen ions (H+(aq)) describe the role of water for acids to exhibit their

properties define acids in terms of the ions they contain or

produce in aqueous solution define the term basicity of an acid state the basicity of different acids such as HCl,

H2SO4, H3PO4, CH3COOH. define bases and alkalis in terms of their reactions

with acids identify the common alkalis found in household

items and in the laboratory describe the characteristics of alkalis and their

typical reactions write chemical and ionic equations for the

reactions of alkalis relate the alkaline properties to the presence of

hydroxide ions (OH−(aq)) describe the corrosive nature of acids and alkalis

and the safety precautions in handling them

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b. Indicators and pH acid-base indicators as

exemplified by litmus, methyl orange and phenolphthalein

pH scale as a measure of acidity and alkalinity

pH = -log[H+(aq)] use of universal indicator and an

appropriate instrument to measure the pH of solutions

state the colours produced by litmus, methyl

orange and phenolphthalein in acidic solutions and alkaline solutions

describe how to test for acidity and alkalinity using suitable indicators

understand the implication of pH scale relate concentration of H+(aq) to the pH value of a

solution suggest and demonstrate appropriate ways to

determine pH values of substances c. Strength of acids and alkalis

meaning of strong and weak acids as well as strong and weak alkalis in terms of their extent of dissociation in aqueous solutions

methods to compare the strength of acids/alkalis

describe the dissociation of acids and alkalis by

using chemical equations relate the strength of acids and alkalis to their

extent of dissociation describe acids and alkalis with the appropriate

terms: strong, weak, concentrated and dilute suggest and perform experiments to compare the

strength of acids or alkalis

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d. Neutralisation and salts bases as chemical opposites of

acids neutralisation as the reaction

between acid and base/alkali to form water and salt only

exothermic nature of neutralisation

preparation of soluble and insoluble salts based on neutralisation

naming of common salts applications of neutralisation

describe neutralisation of acid and alkali write chemical and ionic equations for

neutralisation describe heat change in the process of

neutralisation state the general rules of solubility for common

salts describe the techniques used in the preparation,

separation and purification of soluble and insoluble salts

suggest a method for preparing a salt with suitable starting materials

name the common salts formed from the reaction of acids and alkalis

explain some applications of neutralisation e. Concentration of solutions

concentration of solutions in

mol dm−3 (molarity)

convert the molar concentration of solutions to

g dm−3 perform calculations related to the concentration of

solutions

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f. Volumetric work involving acids and alkalis standard solutions acid-alkali titrations

describe and demonstrate how to prepare solutions

of required concentration by dissolving a solid solute or diluting a concentrated solution

calculate the concentrations of the solutions prepared

describe and demonstrate the techniques of performing acid-alkali titration

apply the concepts of concentration of solution and the results of acid-alkali titrations to solve stoichiometric problems

communicate the procedures and results of a volumetric experiment by writing laboratory report



searching for examples of naturally occurring acids and bases, and their chemical composition.

investigating the actions of dilute acids on metals, carbonates, hydrogencarbonates, metal oxides and metal hydroxides.

designing and performing experiments to study the role of water in exhibiting characteristic properties of acid.

searching for information about the hazardous nature of acids/alkalis.

investigating the action of dilute alkalis on aqueous metal ions to form metal hydroxide precipitates.

investigating the action of dilute alkalis on ammonium compounds to give ammonia gas.

performing experiments to investigate the corrosive nature of concentrated acids/alkalis.

searching for information about the nature of common acid-base indicators.

performing experiments to find out the pH values of some domestic substances.

measuring pH values of substances by using data-logger or pH meter.

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designing and performing experiments to compare the strengths of acids/alkalis.

investigating the temperature change in a neutralisation process.

preparing and isolating salts from acid-alkali or acid-base reactions.

searching for and presenting information on applications of neutralisation.

preparing a standard solution for volumetric analysis.

performing calculations involving molarity.

performing acid-alkali titrations using suitable indicators / data-logger with a pH sensor.

using a titration experiment to determine the concentration of acetic acid in vinegar or the concentration of sodium hydroxide in drain cleaner.

performing calculations on titrations.

writing a detailed report for an experiment involving volumetric analysis.



to develop a positive attitude towards the safe handling, storing and disposing of chemicals, and hence adopt safe practices.

to appreciate the importance of proper laboratory techniques and precise calculations for obtaining accurate results.

to appreciate that volumetric analysis is a vital technique in analytical chemistry.

to appreciate the importance of controlling variables in making comparisons.

to appreciate the use of chemical instruments in enhancing the efficiency and accuracy of scientific investigation.

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STSE Connections


Measures involving neutralisation have been implemented in controlling the emission of nitrogen oxides and sulphur dioxide from vehicles, factories and power stations.

Caustic soda is manufactured by chloroalkali industry which is a traditional chemical raw materials industry.

Volumetric analysis, as one of the essential techniques in analytical chemistry, has been widely applied in testing laboratories and forensic chemistry.

Antacid is a common drug which contains base(s) for neutralising stomach acid and therefore relieving stomachache.

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Topic V Fossil Fuels and Carbon Compounds (24 hours)

Overview Carbon compounds play an important role in industry and in our daily life. Coal and petroleum are two major sources of carbon compounds. In this topic, the main focus is placed on the use of petroleum fractions as fuel and as a source of hydrocarbons. Students should appreciate that the use of fossil fuels has brought us benefits and convenience, such as providing us domestic fuels and raw materials for making plastics, alongside environmental problems like air pollution, acid rain, global greenhouse effect, etc. Eventually, they should realise that human activities can have impacts on our environment. This topic also introduces some basic concepts of organic chemistry like homologous series, functional group, general formula and structural formula, structural isomerism, geometric isomerism and enantiomeric isomerism. Students should be able to give systematic names of alkanes, alkenes, alkanols and alkanoic acids with carbon chains not more than eight carbon atoms. Furthermore, students are expected to know the terms “exothermic reaction” and “endothermic reaction”. Plastics are remarkably useful materials mainly derived from fossil fuels. Many objects used in our daily life are made of plastics. Students should know that plastics is a collective term which embraces a large number of polymers, and that the uses of different plastics can be related to their physical properties which are in turn related to their structures. Students should understand the formation of addition polymers from alkenes. Moreover, they should appreciate that one great advantage of using plastics over other materials, their durability, is also a drawback, as most plastics do not readily degrade in a natural environment. It is therefore necessary to explore appropriate ways for the disposal of plastic waste.

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Learning Objectives and Outcomes Students should learn Students should be able to a. Hydrocarbons from fossil fuels

coal, petroleum and natural gas as sources of fossil fuels and carbon compounds

petroleum as a mixture of hydrocarbons and its separation into useful fractions by fractional distillation

gradation in properties of the various fractions of petroleum

heat change during combustion of hydrocarbons

major uses of distilled fractions of petroleum

consequences of using fossil fuels

describe the origin of fossil fuels describe petroleum as a mixture of hydrocarbons

and its industrial separation into useful fractions by fractional distillation

recognise the economic importance of crude oil as a source of aliphatic and aromatic hydrocarbons (e.g. benzene)

relate the gradation in properties (e.g. colour, viscosity, volatility and burning characteristics) with the number of carbon atoms in the molecules of the various fractions

account for the demand of the various distilled fractions of petroleum

recognise combustion of hydrocarbons as an exothermic chemical reaction

identify the sources of pollution which accompany with the combustion of fossil fuels and explain how they can be avoided

evaluate the impact of using fossil fuels on our quality of life and the environment

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Students should learn Students should be able to b. Homologous series, structural formulae

and naming of carbon compounds Unique nature of carbon Homologous series as illustrated

by alkanes, alkenes, alkanols and alkanoic acids.

Structural formulae and systematic naming of alkanes, alkenes, alkanols and alkanoic acids.

explain the large number and diversity of carbon

compounds with reference to carbon’s unique combination power and ability to form different bonds

explain the meaning of a homologous series understand that members of a homologous series

shows a gradation in physical properties and similarity in chemical properties

write structural formulae of alkanes give systematic names of alkanes extend the knowledge of naming carbon

compounds and writing structural formulae to alkenes, alkanols and alkanoic acids

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Students should learn Students should be able to c. Alkanes and alkenes

Petroleum as a source of alkanes Alkanes Cracking and its industrial

importance Alkenes

distinguish saturated and unsaturated

hydrocarbons from the structural formulae describe the following reactions of alkanes and

write the relevant chemical equations: i. combustion, ii. substitution reactions with chlorine and

bromine as exemplified by reaction of methane and chlorine (or bromine).

recognise that cracking is a means to obtain smaller molecules including alkanes and alkenes

explain the importance of cracking in the petroleum industry

describe the reactions of alkenes with the following reagents and write the relevant chemical equations:

i. bromine, ii. potassium permanganate solution.

demonstrate how to carry out chemical tests for unsaturated hydrocarbons

understand that alkenes are more reactive than alkanes

d. Isomerism

structural isomerism geometrical isomerism as

illustrated by acyclic carbon compounds containing one C=C bond

enantiomerism as exemplified by compounds with one chiral carbon

understand that isomerism occurs when two or

more compounds have the same molecular formula but different structures

recognise and predict the existence of structural isomerism which includes isomers containing the same functional group and isomers containing different functional groups.

recognise the existence of geometrical (cis-trans) isomerism in acyclic carbon compounds resulting from restricted rotation about a C=C bond

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Students should learn Students should be able to show an understanding of structural and

geometrical isomerism by predicting some of the structures of the isomers of given carbon compounds

recognise the existence of enantiomers in compounds with only one chiral carbon

use structural formulae and molecular models to demonstrate the arrangement of atoms in isomers of carbon compounds

e. Addition polymers

Plastics as important materials in the modern world

Monomers, polymers and repeating units

Addition polymerisation Structure and properties of

addition polymers as illustrated by polyethene, polypropene, polyvinyl chloride and polystyrene

Environmental issues related to the use of plastics

recognise that plastics are mainly manufactured

from chemicals derived from petroleum recognise that there are different kinds of plastics recognise that plastics are polymers built up from

small molecules called monomers recognise that alkenes, unsaturated compounds

obtainable from cracking of petroleum, can undergo addition reactions

understand that alkenes and unsaturated compounds can undergo addition polymerisation

describe addition polymerisation using chemical equations

deduce the repeating unit of an addition polymer obtained from a given monomer

deduce the monomer from a given section of the formula of an addition polymer molecule

explain the effect of heat on thermoplastics in terms of their structures

understand the economic importance of plastics and pollution problems associated with the use and disposal of plastic items

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Suggested Learning and Teaching Activities Students are expected to develop the learning outcomes using a variety of learning experiences; some related examples are: searching for and presenting information about the locations of deposits of coal,

petroleum and natural gases in China and other countries. investigating colour, viscosity, volatility and burning characteristics of petroleum

fractions. searching for and presenting information about petroleum fractions regarding their

major uses and the relation between uses and properties. discussing the relationship between global warming and the use of fossil fuels. drawing structural formulae and writing systematic names for alkanes, alkenes, alkanols

and alkanoic acids. building molecular models of simple alkanes, alkenes, alkanols and alkanoic acids. performing experiments to investigate the typical reactions of alkanes and alkenes. performing an experiment on cracking of a petroleum fraction and testing the products. searching for information and presenting arguments on the risks and benefits of using

fossil fuels to the society and the environment. searching for information on alternative sources of energy. predicting the structures of the isomers of given carbon compounds. building molecular models of but-2-enes. building molecular models of butan-2-ol or 2-hydroxpropanoic acid (lactic acid). searching for information or reading articles about the discovery of polyethene and the

development of addition polymers. investigating properties such as the strength and ease of softening upon heating of

different plastics. writing chemical equations for the formation of addition polymers based on given

information. building physical or computer models of addition polymers deducing the monomer from the structure of a given addition polymer. searching for and presenting information on environmental issues related to the use of

plastics. conducting a survey to investigate the quantities and types of solid wastes generated at

home/school and suggest methods to reduce these wastes.

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discussing or debating the issue “Incineration is a better way to handle the solid waste in Hong Kong”.

discussing the environmental advantages and disadvantages of the use of plastics for packaging, and suggesting ways in which the disadvantages could be minimised and any add-on effects of the suggestions

Values and Attitudes Students are expected to develop in particular, values and attitudes, as follows: to appreciate the importance of organising scientific information in a systematic way. to recognise the benefits and impacts of the application of science and technology. to value the need for the conservation of Earth resources. to appreciate the need for alternative sources of energy for a sustainable development

of our society. to value the need for the safe use and storage of fuels. to appreciate the versatility of synthetic materials and the limitations of their use. to show concern for the environment and develop a sense of shared responsibility for a

sustainable development of our society. STSE Connections Students are encouraged to appreciate and to comprehend issues which reflect the interconnections of science, technology, society and the environment; some related examples are: The petroleum industry provides us with many useful products that improve our

standard of living. However, there are risks associated with the production, transportation, storage and usage of fossil fuels.

Emissions from the burning of fossil fuels are polluting the environment and are contributing to long term and perhaps irreversible changes in the climate.

There are many examples of damage uncovered after a long period of the application of science and technology e.g. the pollution problem from using leaded petrol, the disposal problem of plastics. Therefore, it is essential to carefully assess the risks and benefits to society and the environment before they are actually applied in our daily life.

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Topic VI Microscopic World II (11 hours)

Overview This topic builds on Topic II and aims at broadening students’ knowledge and concepts of bonding and structures of substances. Based on the knowledge of covalent and ionic bonding, students will extend their understanding that many bonds are indeed not purely ionic or purely covalent. Students will learn the different natures of intermolecular forces. Consequently they should be able to understand the structures and properties of some molecular crystals. In order to illustrate the interrelation between structures and properties of substances completely, students will study substances with giant covalent structures. Together with the knowledge of giant ionic structure, simple molecular structures and giant metallic structures, students should be able to differentiate the properties of substances with different structures, and to appreciate that knowing the structure of a substance can help us decide its applications. While material chemistry is becoming more important in applied chemistry, this topic provides the basic knowledge for students to further study the development of new materials in modern society.



a. Structure and properties of giant covalent substances

describe giant covalent structures of substances such as diamond, graphite and quartz

state and explain the properties of giant covalent substances in terms of their structures and bonding

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b. Bonding intermediate between ionic and covalent ionic bond with covalent

character bond polarity

understand that the electron transfer in ionic

compounds can be incomplete account for the polarisation of ionic compounds define electronegativity of an atom account for the unequal sharing of electrons in

covalent bonds describe the partial charges of a polar molecule

c. Intermolecular forces

van der Waals’ forces hydrogen bonding

explain the existence of van der Waals’ forces in

non-polar and polar covalent substances state the factors affecting the strength of van der

Waals’ forces between molecules compare the strength of van der Waals’ forces

with that of covalent bonds describe the formation of hydrogen bonding as

exemplified by HF, H2O and NH3 compare the strength of van der Waals’ forces

with that of hydrogen bondings understand the importance of hydrogen bonding in

determining the structures of some materials account for the differences in solubility and

melting point of cis- and trans- butenedioic acids predict some of the properties of an unfamiliar

substance which contains hydrogen bondings d. Structures and properties of molecular

crystals describe the structures of ice, iodine and

fullerenes explain the properties of ice, iodine and fullerenes

in terms of their structures and bondings

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e. Comparison of structures and properties of important types of substances

compare the structures and properties of substances with giant ionic, giant covalent, simple molecular and giant metallic structures

deduce the physical and chemical properties of substances from their structures and bondings, and vice versa

explain applications of substances according to their structures



building models of diamond, graphite, quartz, iodine, ice and fullerenes. manipulating three-dimensional images of crystal structures using computer program. investigating the effect of a non-uniform electrostatic field on a jet of polar and

non-polar liquid. searching for and presenting information about three-dimensional structures, the

discovery and applications of fullerenes. investigating the properties of buckminsterfullerene (C60). investigating the effect of hydrogen bonding on liquid flow. performing an experiment to compare the properties of cis- and trans- butenedioic acids. determining the strength of the hydrogen bonding formed between ethanol molecules. investigating the evaporating rates of substances having different intermolecular forces. investigating the surface tension and viscosity of water in terms of its intermolecular

forces. comparing viscosity of alcohols with different number of hydroxyl groups. searching for and presenting information on the important role of hydrogen bonding in

macromolecules such as DNA and proteins. predicting structures of substances from their properties, and vice versa. reading articles or writing essays on the impacts of the development of modern

materials, such as semiconductors and nanotubes, on our daily life.

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Values and Attitudes Students are expected to develop in particular, values and attitudes, as follows: to appreciate the contribution of science and technology in providing us with useful

materials. to appreciate the usefulness of the concepts of bondings and structures in

understanding phenomena in the macroscopic world, such as the physical properties of substances.

to appreciate the usefulness of models in helping to visualise the structure of substances.

to show curiosity about the latest development of chemical contributions to society and technology.

to appreciate that knowledge about bonding may evolve and become revised as new evidence arisen, e.g. the discovery of the structure of Buckminsterfullerenes.

STSE Connections Students are encouraged to appreciate and to comprehend issues which reflect the interconnections of science, technology, society and the environment; some related examples are: Carbon nanotube composites are being developed for use in aerospace and other

high-performance applications such as body armor, sports equipment, and in the auto industry.

Mass production of fullerenes has to be made commercially viable before their use in the fields of electronic, semiconductors and pharmaceuticals can be implemented.

Some specialised new materials have been created on the basis of the findings of research on the structure of matter, chemical bonding, and other properties of matter (e.g. Bulletproof fabric, superconductors, superglue).

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Topic VII Redox Reactions, Chemical Cells and Electrolysis

(26 hours)

Overview Chemical reactions are associated with the release or absorption of energy, often in the form of heat, light and electrical energy. In a chemical cell, chemical energy is converted to electrical energy. The flow of electrons in an external circuit indicates the occurrence of reduction and oxidation (redox) at the electrodes. To understand the chemistry involved in a cell, the concept of redox is introduced in this topic. Students will carry out investigations involving common oxidizing and reducing agents. Meanwhile, they will learn how to write chemical equations for redox reactions. With the concepts related to redox reactions, students should be able to understand the reactions occurring in more complicated chemical cells and the processes involved in electrolysis. Students should also appreciate that the feasibility of a redox reaction can be predicted by comparing the positions of the species in the electrochemical series. In addition, students should be able to predict products in electrolysis according to different factors affecting the preferential discharge of ions. The concepts related to redox reactions find a number of applications in industrial chemistry and daily life. Through information search and critical reading of topics about electrochemical technology, students should appreciate the contribution of chemical knowledge to technological innovations, which in turn improves our quality of living. On the other hand, students should also be able to assess environmental impacts and safety issues associated with these technologies.

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a. Chemical cells in daily life primary cells and secondary cells uses of chemical cells in relation

to factors such as size, price and life-expectancy

distinguish between primary and secondary cells describe the characteristics of common primary

and secondary cells: i. zinc-carbon cell ii. alkaline manganese cell iii. silver oxide cell iv. nickel-cadmium (Ni-Cd) cell v. lithium cell

justify uses of different chemical cells for particular purposes

evaluate the environmental impacts of using dry cells

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b. Reactions in chemical cells chemical cells consisting of:

i. two metal electrodes and an electrolyte

ii. metal-metal ion half-cells and salt bridge/porous device

changes occurring at the electrodes and electron flow in the external circuit

ionic half equations and overall cell equations

describe and demonstrate how to build simple

chemical cells by using metal electrodes and electrolytes

measure the maximum voltage produced by a chemical cell

account for the problems associated with a simple chemical cell consisting of two metal electrodes and an electrolyte

explain the functions of salt bridge describe and demonstrate how to build simple

chemical cells using metal-metal ion half-cells and salt bridges

explain the differences in voltages produced from chemical cells when different metal couples are used as electrodes

write ionic half equations representing the reaction at each half cell of simple chemical cells

write overall equations for simple chemical cells predict the electron flow in the external circuit and

the chemical changes of simple chemical cells

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c. Redox reactions oxidation and reduction common oxidizing agents,

including concentrated sulphuric acid and nitric acid of different concentrations

common reducing agents oxidation numbers balancing redox equations Common redox reactions

i. reactions in a zinc-carbon cell

ii. reactions in chemical cells consisting of half cell(s) other than metal-metal ion systems

iii. reactions in a fuel cell

identify redox reactions, oxidizing agents and

reducing agents using i. changes in oxygen or hydrogen, or ii. changes in electron(s), or iii. changes in oxidation numbers

construct the general trend for the reducing power of metals and the oxidizing power of metal ions

list the trend for the oxidizing power of non-metals

relate the trends of the reducing power and oxidizing power of chemical species to the electrochemical series

describe the chemical changes of some common oxidizing agents and reducing agents

assign oxidation numbers to the atoms of compounds

balance half equations of reduction and oxidation balance redox equations by using ionic half

equations or changes in oxidation numbers describe and construct chemical cells with inert

electrodes predict the chemical changes at each half cell of

the chemical cells with inert electrodes write ionic half equation for each half cell and

overall ionic equation for the chemical cells with inert electrodes

describe the structure of a zinc-carbon dry cell write ionic half equation at each electrode and

overall reaction of a zinc-carbon dry cell

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understand the principles of fuel cells as exemplified by hydrogen-oxygen fuel cell

write ionic half equation at each electrode and overall reaction of a hydrogen-oxygen fuel cell

d. Electrolysis

electrolysis as the decomposition of substances by electricity as exemplified by electrolysis of i. dilute sulphuric acid, ii. sodium chloride solutions of

different concentrations, iii. copper(II) sulphate solution

anodic and cathodic reactions preferential discharge of ions in

relation to the electrochemical series, concentration of ions and nature of electrodes

Industrial applications of electrolysis: i. electroplating, ii. purification of copper

describe the materials needed to construct an

electrolytic cell predict products at each electrode of an

electrolytic cell with reference to the factors affecting the preferential discharge of ions

describe the anodic and cathodic reactions, overall reaction and observable changes of the electrolyte in electrolytic cells

understand the principles of electroplating and purification of copper

describe the anodic and cathodic reactions, overall reaction and observable changes of electrolyte in electroplating and purification of copper

evaluate the environmental impacts of the electroplating industry

e. Importance of redox reactions in

modern ways of living development of new technology

applying concepts related to redox reactions as exemplified by fuel cell technology and rechargeable lithium cells

recognise the use of redox reactions in a wide

range of industries and technological development discuss the role of redox reactions in modern ways

of living

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Suggested Learning and Teaching Activities Students are expected to develop the learning outcomes using a variety of learning experiences; some related examples are: making decision on the choice of chemical cells in daily life based on available

information. making simple chemical cells and measuring their voltages. writing ionic half equations. performing experiments to investigate redox reactions. determining oxidation numbers of atoms in chemical species. balancing redox equations by using ionic half equations or by using oxidation

numbers. investigating redox reactions of concentrated sulphuric acid with metals. investigating redox reactions of nitric acid of different concentrations with metals. searching for and presenting information about the applications of fuel cells. predicting changes in chemical cells based on given information. viewing or constructing computer simulations illustrating the reactions in chemical

cells. performing experiments to investigate changes in electrolysis. searching for and presenting the adverse impacts of electroplating industry on the

environment. designing and performing electroplating experiments. reading articles about new development of fuel cell technology and lithium cells. discussing the feasibility of using alcohol fuel cells in portable electronic devices.

Values and Attitudes Students are expected to develop in particular, values and attitudes, as follows: to value the contribution of technological innovations to the quality of living. to appreciate the usefulness of the concept of oxidation number in the study of redox

reactions. to develop a positive attitude towards the safe handling, storing and disposing of

chemicals, and hence adopt safe practices. to value the need for assessing the impacts of technology on our environment.

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STSE Connections Students are encouraged to appreciate and to comprehend issues which reflect the interconnections of science, technology, society and the environment; some related examples are: Various breath testing technology, such as passive alcohol sensors, preliminary breath

tests, and evidentiary breath tests (e.g. the intoximeter EC/IR) all utilise fuel cell technology to detect alcohol.

Many different fuel cells are being developed for possible commercial uses, such as providing power to electrical appliances, automobiles, home and factories.

Lithium cell chemistry variants, such as lithium-ion battery, lithium-ion polymer battery, lithium cobalt battery, lithium manganese battery and lithium nickel battery, have been developed to cope with the needs of a wide range of consumer products.

Many electrolytic processes are involved in industrial processes, e.g. refining of metals, chloroalkali industry.

The development of electrolysis in extracting reactive metals is closely related to the human history.

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Topic VIII Chemical reactions and energy (9 hours)

Overview Chemical reactions are accompanied by energy changes, often in the form of heat. The energy absorbed or released by a chemical system may take different forms. Basic concepts of chemical energetics and enthalpy terms will be introduced. Practical work on simple calorimetric method and quantitative treatment of the Hess’s law can help students better understand the concepts of energetics. However, the use of equipment like the bomb calorimeter is beyond the expectation of study at this level. Prior knowledge of quantitative treatment of heat change based on heat capacity calculation is assumed. Learning Objectives and Outcomes


a. Energy changes in chemical reactions

• conservation of energy • endothermic and exothermic

reactions and their relationship to breaking and forming of bonds

• account for energy changes in chemical reactions in terms of the concept of conservation of energy

• describe enthalpy change, ∆Η, as heat change at constant pressure

• explain diagrammatically the nature of exothermic and endothermic reactions in terms of enthalpy change

• explain the nature of exothermic and endothermic reactions in terms of breaking and forming of chemical bonds

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b. Standard enthalpy change of neutralisation, hydration, solution, formation and combustion

• explain and use the terms: enthalpy change of reaction and standard conditions, with particular reference to neutralisation, hydration, solution, formation and combustion

• carry out experimental determination of enthalpy changes using simple calorimetric method

• calculate enthalpy changes from experimental

results, including the use of the relationship: ∆Η = mc∆T

c. Hess’s law

• use of Hess’s law to determine enthalpy changes which cannot be easily determined by experiment directly

• enthalpy level diagram • calculations involving enthalpy

changes of reactions

• apply Hess’s law to construct simple enthalpy change cycles and enthalpy level diagrams

• carry out calculations involving such cycles and relevant energy terms, with particular reference to determining enthalpy change that cannot be found by direct experiment

Suggested Learning and Teaching Activities Students are expected to develop the learning outcomes using a variety of learning experiences; some related examples are: using appropriate method and techniques to design and carry out determination of

standard enthalpy change of (a) hydration of S2O32− , (b) acid-base neutralisation and

(c) combustion of alcohols. designing enthalpy change cycles and enthalpy level diagrams to quantitatively relate,

according to Hess’s law, reaction enthalpy changes and other standard enthalpy changes.

discussing the limitations of simple calorimetric methods as opposed to more sophisticated techniques.

performing calculations on standard enthalpy change of reactions involving (a) standard enthalpy of formation, (b) standard enthalpy of combustion, and (c) other standard enthalpy terms.

finding out different approaches in solving problems on standard enthalpy changes in chemical reactions.

investigating the chemistry involved in hand-warmers or cold-packs.

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Values and Attitudes Students are expected to develop, in particular, values and attitudes, as follows: to value the need to understand in a systematic way heat changes in chemical reactions. to appreciate the importance of interdisciplinary relevance, e.g. involvement of prior

knowledge of quantitative treatment in thermal physics in enthalpy change calculations.

to accept quantitative experimental results within tolerance limits. STSE Connections Students are encouraged to appreciate and to comprehend issues which reflect the interconnections of science, technology, society and the environment; some related examples are: Humans have been making efforts to discover more efficient release of thermal energy

from chemical reactions, e.g. combustion of fuels. The ever-increasing use of thermal energy from chemical reactions has impacts on

technology and the environment, e.g. energy crisis and global warming.

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Topic IX Rate of Reaction (9 hours)

Overview Rate of reaction is a fundamental concept in the study of chemistry and in daily life. Students have had a lot of experience with different rates of change in their previous learning. For example, students should know that rusting is a slow process but the reaction of hydrogen and oxygen can be extremely rapid. Furthermore, there is always a strong need for ways to control the rates of change. In short, this topic attempts to help students to build up concepts related to rate of reaction. Students will learn different methods that can be used to follow the progress of a reaction and the factors that affect rate of reaction. Equipment and apparatus in the school laboratory should be able to provide students with such experience. With the use of more sophisticated instruments such as suitable sensors and data-logging system, investigations or practical work can be performed in a more accurate and efficient manner. Catalysis plays an important role both in research and in chemical industries. Students should be aware of the fact that practically all chemical reactions in large-scale chemical plants involve the use of catalysts and that reactions occurring in living systems are catalysed by enzymes. A further study of catalysis is found in Topic XIII “Industrial chemistry”. Molar volume of gases at room temperature and pressure is included in this topic for a complete quantitative stoichiometric treatment of chemical equation at this level of study.

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a. Rate of chemical reaction methods of following the progress

of a chemical reaction instantaneous and average rate

design and plan experiments to follow the

progress of a reaction perform investigations involving the following

techniques to follow the progress of a reaction: i. titrimetric analysis ii. measurement of the changes in: volume /

pressure of gases, mass of a mixture, colour intensity of a mixture and transmittance of light

construct and interpret a graph to show the progress of a reaction based on evidence collected through first-hand investigations and other sources

determine instantaneous and average rate from a suitable graph

b. Factors affecting rate of reaction

concentration temperature surface area catalyst

design and perform experiments to study the

effects of i. concentration ii. temperature iii. surface area, and iv. catalyst on rate of reactions

analyse data, interpret results and draw conclusions based on evidence collected through first-hand investigations and other sources

account for the qualitative effect of changes in concentration, surface area and temperature on the rate of reaction

appreciate the importance of catalyst in chemical industries and biological systems

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c. Molar volume of gases at room temperature and pressure (r.t.p.) calculations involving molar

volume of gases

deduce the volume of one mole of all gases at r.t.p.

as 24 dm3 perform stoichiometric calculations involving

molar volume of gases at r.t.p.

Suggested Learning and Teaching Activities Students are expected to develop the learning outcomes using a variety of learning experiences; some related examples are: • searching for information on accident(s) caused by failure of controlling reaction rate. • selecting and explaining the appropriateness of using titration, volume measurement,

colorimetry, pH measurement, pressure change or gravimetric analysis to meet the requirement of following the progress of a chemical reaction.

• discussing the nature of rate studies with respect to methods of “quenching” and “on-going”.

• using appropriate methods, skills and techniques, like the micro-scale chemistry technique and data-loggers, to study the progress of a reaction.

• performing the following experiments to follow the progress of the reactions: (a) Titration: alkaline hydrolysis of esters (b) Conductometric titration: reaction between Ba(OH)2(aq) and H2SO4(aq) (c) Volume or mass measurement: reaction of CaCO3 with dilute acids (d) Colorimetry: oxidation of C2O4

2−(aq) ion by acidified KMnO4(aq) (e) Transmittance of light: S2O3

2−(aq) and dilute acids (f) Pressure measurement: data-logging of the experiment Mg(s) with dilute acids

• investigating the effect of change in concentration of reactant, temperature, surface area, or the use of catalyst on reaction rate.

• performing calculations involving the constant of molar volume of gases at room temperature and pressure viz. 24 dm3.

• performing experiments to determine the molar volume of a gas. • searching for information or reading articles on airbag of vehicles.

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Values and Attitudes Students are expected to develop in particular, values and attitudes, as follows: to value the need for controlling reaction rates for the betterment of human

advancement. to value the need for identifying crucial variable for situation. to appreciate the diversity in approaches to solving a problem.

STSE Connections Students are encouraged to appreciate and to comprehend issues which reflect the interconnections of science, technology, society and the environment; some related examples are: Control of metal corrosion possesses its socioeconomic importance and environmental

relevance. The use of catalysts has been very important to industry and in the medical field. Research into reaction rate have led to a positive contribution to society, e.g. airbags in

vehicles. Researches into reaction rate are linked with development of lethal weapons.

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Topic X Chemical Equilibrium (10 hours)

Overview In general, chemical reactions are either reversible or irreversible. The concept of a state of equilibrium for the majority of reversible reactions is fundamental in chemistry. Students should appreciate the dynamic nature of chemical equilibrium, in particular the shifting of equilibrium position when a system at equilibrium is subjected to a change. It is therefore important to control variables such as pressure, concentration and temperature in an industrial process so as to establish the optimal reaction conditions. A more in-depth treatment of the aforementioned concepts will be found in Topic XIII “Industrial chemistry”. The equilibrium law provides a quantitative relationship of the concentrations of the reactants and products in system at equilibrium. Students should understand the equilibrium constant Kc and its mathematical treatment in relation to the stoichiometry of reactions. Furthermore, detailed treatment of equilibrium systems involving redox and acid-base reactions are beyond the expectation of this level of study. However, these systems can be regarded as further examples of chemical equilibrium. The concept of chemical equilibrium finds a number of applications in daily life. Information search and extensive reading of related topics can help students better build up their understanding of the concepts involved as well as the relationship of the different types of equilibrium.


Students should learn Students should be able to a. Dynamic equilibrium

characteristics of dynamic equilibrium

describe using suitable examples reversible and

irreversible reactions define a chemical reaction existing in a state of

dynamic equilibrium describe characteristics of a system existing in

chemical equilibrium

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Students should learn Students should be able to b. Equilibrium constant

equilibrium constant expressed in terms of concentrations (Kc)

express the mathematical relationship between

concentrations of reactants and products at equilibrium and Kc

c. The effect of changes of concentration

and temperature on chemical equilibria Changes in concentration result in

the adjustment of the system without changing the value of Kc

A change in temperature results in possible changes in Kc of the system

understand that the value of Kc for a equilibrium system is a constant irrespective of change in concentration of reactants and products

derive inductively the relation of temperature and the value of Kc from given data sets

perform calculations involving Kc perform practical work on the determination of Kc

of selected chemical system at equilibrium deduce the effects of changes of concentration and

temperature on the position of a chemical equilibrium

predict qualitatively the effect of temperature on

the position of equilibrium from the sign of ∆Η for the forward reaction

d. Applications of equilibrium systems in

chemical industries

describe examples of chemical equilibrium employed in industry

state conditions of equilibrium for important chemical industries as exemplified by contact process and Haber process

Suggested Learning and Teaching Activities Students are expected to develop the learning outcomes using a variety of learning experiences; some related examples are: • searching for information on issues related to chemical equilibrium. • investigating examples of irreversible and reversible reactions. • investigating the dynamic nature of chemical equilibrium. • designing and performing experiments to investigate the qualitative effects of pH on

chemical equilibrium systems such as Br2(aq) + H2O(l) HOBr(aq) + H+(aq) + Br−(aq) or Cr2O7

2−(aq) + H2O(l) 2CrO42−(aq) + 2H+(aq)

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• investigating the effect of changes of concentration and temperature on chemical equilibrium using a computer simulation.

• performing calculations related to equation stoichiometry and the equilibrium constant Kc by either evaluating Kc from equilibrium concentrations or vice versa.

• designing and performing experiment to determine Kc of a chemical equilibrium system such as esterification of alkanol and alkanoic acid.

• investigating equilibria of (a) SCN−(aq) + Fe3+(aq) [Fe(SCN)]2+(aq) and (b) N2O4(g) 2NO2(g) to study the shift of position of equilibrium upon changing concentration, temperature or pressure.

• describing shift in positions of equilibrium and the relative amounts of reactants and products in the newly established equilibrium.

• investigating the relationship of temperature and the value of Kc from given data sets. • describing optimum equilibrium conditions for the Haber process and the contact

process. Values and Attitudes Students are expected to develop in particular, values and attitudes, as follows: • to value the need of quantitative treatment of chemical equilibrium systems for a better

control of product formation. • to recognise the fact that the majority of reactions employed in chemical industries are

reversible. • to appreciate advantages of qualitative treatment and quantitative treatment in solving

different problem. STSE Connections Students are encouraged to appreciate and to comprehend issues which reflect the interconnections of science, technology, society and the environment; some related examples are: Applications of chemical equilibrium have been playing an important role in

industries. Chemical equilibrium has been applied in a wider context in various scientific and

technological areas.

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Topic XI Chemistry of carbon compounds (22 hours)

Overview Organic chemistry is a very important branch of chemistry as judged from the uniqueness of carbon and ubiquitousness of carbon compounds. Together with the basic concepts and knowledge acquired in junior secondary course and in Topic V and Topic VI, students can build up concepts related to the structural characteristics of some common carbon compounds. Furthermore, students are expected to be able to use systematic names and trivial names of carbon compounds to communicate knowledge and understanding in study and in daily life. In this topic, students will learn about the chemistry of a number of functional groups. They should be able to give systematic names of alkanes, alkenes, haloalkanes, alcohols, aldehydes and ketones, carboxylic acids, esters, amides and amines, with carbon chains not more than eight carbon atoms. Through a study of the reactions of the functional groups (including the reagents, reaction conditions, products and observations), students can make use of chemical methods to distinguish different functional groups and to identify unknown carbon compounds. Besides, students should recognise the relationships between different functional groups and be aware of the most important applications of organic chemistry, i.e. the synthesis of useful carbon compounds through inter-conversions between different functional groups. To further their understanding about the reactions included in this topic, students should carry out experimental work of simple organic synthesis. The use of reaction mechanisms to explain how carbon compounds react is beyond the expectation of study at this level. In this topic, the term “detergent” denotes two classes of substances which assist cleaning: soaps and soapless detergents. Students should appreciate that the structure of detergents consists of both hydrophobic and hydrophilic parts. These structural characteristics of detergents render the emulsifying properties of detergents. Students should have a basic understanding of the differences in the cleaning abilities of soaps and soapless detergents, and the environmental problems associated with their uses.

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a. Introduction to selected homologous series Homologous series Structural formulae and

systematic naming

give systematic name, general formulae,

condensed formulae and structural formulae for: alkanes, alkenes, haloalkanes, alcohols, aldehydes and ketones, carboxylic acids, esters, amides and amines

draw the structures of the compounds based on their systematic names

understand the effects of functional groups and the length of carbon chains on physical properties of carbon compounds.

identify some nonsystematic names for carbon compounds (e.g. formaldehyde, chloroform, acetone, isopropyl alcohol, acetic acid)

b. Typical reactions of various functional

groups Alkanes Alkenes Haloalkanes Alcohols Aldehydes Ketones Carboxylic acids Esters Amides

describe the following reactions, in terms of

reagents, reaction conditions and observations, and write the relevant chemical equations: i. Alkane: substitution with halogens ii. Alkene: addition of hydrogen, halogens and

hydrogen halides iii. Haloalkanes: substitution with OH－(aq) iv. Alcohols: substitution with halides;

dehydration to alkenes; oxidation of primary alcohols to aldehydes and carboxylic acids; oxidation of secondary alcohols to ketones

v. Aldehydes and ketones: oxidation and reduction using K2Cr2O7 and LiAlH4 respectively

vi. Carboxylic acids: esterification, reduction and amide formation

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vii. Esters: hydrolysis viii. Amides: hydrolysis

predict and correctly name the products of the above reactions

c. Inter-conversions between the

functional groups

use the reactions described in (b) to transform one functional group into another

state the reagents and conditions to accomplish conversions of carbon compounds based on the organic reactions described above

predict the major organic products of reactions, with given starting materials, reagents and conditions

d. Synthesis of important organic

substances synthetic routes for important

organic substances laboratory preparations of simple

carbon compounds purification and identification of

major organic products percentage yield

recognise that aspirin is used as a drug to relief

pain, reduce inflammation and fever, and the risk of heart attack

recognise that detergents can be made from chemicals derived from petroleum

recognise the importance of ethanoic acid for its wide applications as an acid, a solvent, reagent and an intermediate for making other chemicals (e.g. acetate rayon), etc.

propose practicable pathways for the synthesis of important organic substances such as soaps and detergents, aspirin and ethanoic acid from suitable starting materials

propose suitable apparatus, conditions and safety precautions for carrying out simple organic preparation in the laboratory

demonstrate how to carry out laboratory preparations and purification of simple carbon compounds such as ethanoic acid and an ester

identify the major organic products based on physical (b.p. and m.p.) and chemical properties of

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the compounds calculate the percentage yield of an organic

product obtained from a reaction e. Structure and properties of soaps and

detergents Detergent Structures of soaps and soapless

detergents Emulsifying properties of

detergents Cleaning abilities of soaps and

soapless detergents Environmental problems

associated with the use of detergents

explain the meaning of the term ‘detergent’ as a

substance which helps to remove dirt by i. its ability to act as a wetting agent, ii. its emulsifying action

explain the emulsifying properties of detergents in relation to their structures

compare the cleaning abilities of soaps and soapless detergents in hard water

explain the environmental problems associated with the use of detergents.

f. Importance of carbon compounds in

living things

carbon compounds found in living things: carbohydrates, lipids and proteins

recognise the functional groups present in carbohydrates, lipids and proteins

Suggested Learning and Teaching Activities Students are expected to develop the learning outcomes using a variety of learning experiences; some related examples are: building molecular models of compounds with different functional groups. comparing physical properties of the following compounds: propane, butanes, pentanes,

ethanol, propan-1-ol and butan-1-ol. searching for nonsystematic names of common carbon compounds. inspecting reaction schemes and important synthetic routes in organic chemistry. inspecting or writing reaction schemes that summarise all the reactions described. planning routes for synthesis of simple carbon compounds from precursors that are

readily available by analysing the structure of the target molecules. searching for and presenting information about the synthetic routes of some important

organic substances commonly found in our daily life.

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performing a small scale synthesis of ethanoic acid or ethyl ethanoate. preparing soap from a fat or an oil, and testing its properties. searching for and presenting information on cationic surfactants and neutral

surfactants. performing an experiment to prepare 2-chloro-2-methylpropane from

2-methylpropan-2-ol. searching for and presenting information on the discovery of aspirin and its

applications. performing an experiment to analyse commercial aspirin tablets. searching for and presenting information on the historical development of detergents. performing experiments to investigate the wetting ability and emulsifying action of

detergents. designing and carrying out experiments to compare the cleaning abilities of soaps and

soapless detergents. searching for and presenting information on environmental issues related to the use of

detergents. Values and Attitudes Students are expected to develop in particular, values and attitudes, as follows: to appreciate that science and technology provide us with useful products. to appreciate the versatility of synthetic materials and the limitations of their use. to be aware of the hazards associated with the use and disposal of carbon compounds

in the laboratory (e.g. combustibility and toxicity) and the precautions to be taken. to show concern for the conservation of our environment and develop a sense of shared

responsibility for a sustainable development of our society.

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STSE Connections Students are encouraged to appreciate and to comprehend issues which reflect the interconnections of science, technology, society and the environment; some related examples are:

Often more than one synthetic route may be available to prepare a particular carbon compound. However, some synthetic routes may have undesirable effects to human health and our environment. The best synthetic route may not be the one with the fewest steps or the lowest cost. It is essential to apply our knowledge in organic chemistry so that useful organic products are developed and manufactured by safe, economic and environmentally acceptable routes.

The search for new carbon compounds often requires the synthesis of hundreds of compounds which are variations on a basic structure. Some synthesised compounds may have certain useful aspects, but with dangerous side effects which prohibit their general use. It is often necessary to look for other compounds with a similar structure but without the side effects.

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Topic XII Patterns in the Chemical World (10 hours)

Overview Through the study of this topic, students can develop an understanding about the importance of the Periodic Table in chemistry. Knowledge and concepts about the periodic trends of physical properties of some elements and the periodic relationship of acid-base properties of selected oxides are required. Students can also develop knowledge and concepts about the properties of selected transition metals and their compounds. The importance of the use of transition metals in industries and other applications will be discussed.



a. Periodic variation in physical properties of the elements Li to Ar variation in nature of bonding variations in melting point and

electrical conductivity

understand that elements in the Periodic Table are

arranged in order of ascending atomic number describe the nature of bonding and structures of

elements of Group I through Group 0 of the Periodic Table

describe the periodic variations of melting point and electrical conductivity of the elements

interpret the variations in melting point and in electrical conductivity in terms of the bonding and structure of the elements, viz. the presence of giant metallic structures, giant covalent structures and simple molecular structures

b. Variations in acid-base properties of the

oxides of the elements Na to Cl account for the nature of bonding and

stoichiometric composition of oxides of the elements Na to Cl

describe the pattern of variation of behaviour of oxides of the elements Na to Cl in water and the corresponding acid-base properties

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c. General properties of transition metals coloured ions variable oxidation states catalytic properties

identify positions of the transition metals in the Periodic Table

describe that most aqueous ions of transition metals are coloured, e.g. Fe3+(aq), Cr3+(aq), Cu2+(aq)

describe that all transition metals can exist in more than one oxidation states in their

compounds, e.g. Fe2+ and Fe3+; MnO4− , Mn2+ and

MnO2 describe that most transition metals and their

compounds can be used as catalysts describe the importance of transition metals

Suggested Learning and Teaching Activities Students are expected to develop the learning outcomes using a variety of learning experiences; some related examples are: • searching for information on developments of the Periodic Table. • searching for information and interpreting the trends of physical properties of elements

in Period 2, 3, and 4 viz. density and solubility in water. • investigating the trends of the melting point and the electrical conductivity of elements

across a period. • investigating the behaviour of oxides of the elements Na to Cl in water and the

corresponding acid-base properties. • investigating the inter-conversion of oxidation states of transition metal ions such as

the vanadium(V), vanadium(IV), vanadium(III) and the vanadium(II) ions. • investigating the iron content in some commercial ‘iron tablets’. • investigating the catalytic activity of transition metal ions on some redox reactions, e.g.

iron(II) ion as catalyst for the reaction between I−(aq) and S2O82−(aq) ions, silver nitrate

in the oxidation of ethanol using acidified Cr2O72−.

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Values and Attitudes Students are expected to develop in particular, values and attitudes, as follows: to value the need of global examination of phenomena from individual investigations

and generalisation into trends of variations. to appreciate the pattern-wise variations that occur in nature. to appreciate human endeavour in searching for a means of increasing yield of

reactions. STSE Connections Students are encouraged to appreciate and to comprehend issues which reflect the interconnections of science, technology, society and the environment; some related examples are: Transition metals are used as catalysts in the fields of technology, medical research and

industry. Transition metal ions have played an important role in maintaining body health. Myoglobin and haemoglobin are physiological important in terms of their ability to

bind molecular oxygen. The ability to bind oxygen is related to the deep red iron-containing prosthetic group of the molecule.

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Elective Part (Total 52 hours, select any 2 out of 3)

Topic XIII Industrial Chemistry (26 hours) Overview This topic aims to provide students opportunities to advance their knowledge and understanding of some fundamental chemistry principles, and to develop an understanding of industrial chemistry. A study of some important industrial processes like Haber process, chloroalkali industry and Fischer-Tropsch process are required. Students are expected to have a more in-depth understanding of chemical kinetics including heterogeneous and homogeneous catalysis. In this connection, it is helpful to link the content of this topic with relevant topics in the compulsory part. Through the learning of industrial chemistry, students can appreciate how chemists apply chemistry principles and scientific method to solve authentic problems in industry, and to optimise chemical processes. In addition, students should be able to experience how chemists make use of computer modeling to simulate and control a chemical plant. Furthermore, students should be able to evaluate the role of chemistry in society from different perspectives, and to develop concepts and understanding of green chemistry for the management and control of the impact of industrial processes on our environment. Students are also expected to develop skills related to quantitative chemistry by constructing and interpreting graphs, and performing calculations. Learning Objectives and Outcomes


a. Importance of industrial processes Development of synthetic

products for modern ways of living

discuss the advantages and disadvantages of using

industrial processes for manufacturing products from social, economic and environmental perspectives

evaluate recent progress in industrial processes to solve problems of inadequate or shrinking supply of natural products

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b. Rate equation Rate equation determined from

experimental results

determine rate equation of a chemical reaction by

gathering first-hand experimental data understand the interrelationship between reaction

rate, rate constant, concentrations of reactants and order of reaction

c. Activation energy relation of activation energy and

catalysis Explanation of the effect of

temperature change on reaction rate in terms of activation energy

Arrhenius equation

RT 2.3aE

constantog k −=λ

understand that catalysts work by providing an

alternative reaction route of lower activation energy

explain the relationship between temperature and reaction rate using energy profile of a chemical reaction

gather first-hand experimental data needed to determine the activation energy of a chemical reaction

determine the activation energy of a chemical reaction using the Arrhenius equation by calculations or through a graphical method

d. Catalysis and industrial processes

Meaning and characteristics of catalyst

Homogeneous and heterogeneous catalysts

describe the characteristics of catalysts using

suitable examples describe the applications of catalysis in industrial

processes by examples such as iron in the Haber process, catalytic converters in car exhaust systems, and enzymes in the production of alcoholic drinks

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e. Industrial processes Conversion of raw materials to

consumer products as illustrated by the production of fertilisers

Applications of principles of electrochemistry in industry as exemplified by the processes in chloroalkali industry

Processes involving in making synthetic products from different raw materials as exemplified by the Fisher-Tropsch synthesis

Social, economic and environmental considerations of industrial processes

describe feed stocks, principles, reaction

conditions, procedures and products for processes involving in the production of ammonia

describe the process of conversion of ammonia to fertilisers

explain the underlying physicochemical principles involved in making ammonia

explain how the output of Haber process can be maximised

calculate the percentage yield of a chemical reaction

describe and explain the practices associated with use of raw materials, transportation and storage of products using the case of the production of fertilisers as an example

discuss and explain the importance of fertilisers to our world

explain the underlying chemical principles involved in chloroalkali industry

describe the importance of chloroalkali industry explain the processes of using different feed

stocks to make synthetic products using the case of Fisher-Tropsch synthesis as an example

describe the importance of Fisher-Tropsch synthesis

describe and explain criteria (including safety and potential environmental impact) involved in the selection of a site for establishing a chemical industry

describe social, economic and environmental considerations of industrial processes as illustrated by Haber process, chloroalkali industry and Fisher-Tropsch synthesis

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f. Green Chemistry Principles and concepts of green

chemistry Green chemistry practices as

exemplified by the manufacture of acetic acid (ethanoic acid)

describe relation of sustainable development and

green chemistry calculate the atom economy of a chemical

reaction relate green chemistry principles and practices

used in the industrial processes evaluate industrial processes using green

chemistry principles

Suggested Learning and Teaching Activities Students are expected to develop the learning outcomes using a variety of learning experiences; some related examples are: performing experiments to determine activation energy of a chemical reaction. designing and performing experiments to investigate ways to change the rate of a

reaction with a suitable catalyst. performing calculations related to activation energy, percentage yield and atom

economy. reading articles on the importance of and various attempts used for nitrogen fixation. using computer modeling to study the process of an industrial process and to control

the production of a chemical plant. analysing an industrial process from scientific, social, economic and environmental

perspectives. discussing the feasibility of using the principles of green chemistry for daily life

applications of chemistry. searching for and presenting information about the greening of acetic acid

manufacture. decision making exercise on selecting the location for a chemical industry. reviewing industrial processes using green chemistry principles.

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Values and Attitudes Students are expected to develop in particular, values and attitudes, as follows: to appreciate the significance of knowledge and understanding in fundamental

chemical principles on the production of synthetic materials for human beings. to value the need for safe transport and storage of hazardous substances like ammonia,

acetic acid, hydrogen, chlorine and sodium hydroxide. to show concern for the limited supply of natural products and appreciate the

contribution of industrial chemistry to our society. to recognise the importance of catalyst in chemical industry. to show willingness to adopt green chemistry practices.

STSE Connections Students are encouraged to appreciate and to comprehend issues which reflect the interconnections of science, technology, society and the environment; some related examples are: Consumers have a great demand for products like optical brighteners, but at the same

time, the manufacture process produces effluent, particularly volatile organic compounds (VOCs), which is not environmental friendly.

Chemists developed the process for the mass production of fertilisers to relieve problems related to inadequate supply of food.

Green chemistry is a “reduction” process, which aims to reduce materials, energy, waste, cost, environmental impact, volatile organic compounds, risk and hazard, and plant. Nevertheless, the wide adoption of green chemistry practices is often economically and technologically less viable at the present.

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Topic XIV Materials Chemistry (26 hours)

Overview This topic aims to provide opportunities to students to broaden their knowledge and understanding on materials chemistry. Studies of some important materials like polymers, alloys, liquid crystals, ceramics and nanomaterials are required. Students are expected to have a more thorough understanding of polymers including thermoplastics, thermosetting plastics, polymeric biomaterials and biodegradable plastics. In this connection, it is helpful to link the content with relevant topics in the compulsory part. Through the learning of materials chemistry, students can appreciate the contributions of chemists in the development of new materials to replace those that have been deemed no longer satisfying our needs in the modern way of living. Furthermore, students are expected to appreciate that through the applications of green chemistry concepts in the production processes of synthetic materials, the harm either to our health or to the environment can be reduced or even eliminated.



a. Naturally occurring polymers Structure and properties of

cellulose, chitin and silicates

explain properties of cellulose and chitin in

terms of their structures compare structural features of cellulose and

chitin explain effect of structures on properties of

silicates as exemplified by chain silicates, sheet silicates and network silicates

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b. Synthetic polymers and plastics Addition polymerisation Formation and uses of addition

polymers like polytetrafluoroethane (PTFE) and polymethyl methylcrylate (PMMA)

Formation and uses of adhesives such as cyanoacrylate (superglue)

Condensation polymerisation Formation and uses of polyesters

and polyamides Polymeric biomaterials such as

polylactide (PLA) Effect of structure on properties

such as density, hardness, rigidity, elasticity and biodegradability as exemplified by i. high density polyethene and

low density polyethene ii. nylon and Kevlar iii. vulcanisation of polymers iv. biodegradable plastics

Plastics fabrication processes - injection moulding, blow moulding, extrusion, vacuum forming and compression moulding

explain the meaning of the terms “thermosetting

plastics” and “thermoplastics” explain the similarities and differences of addition

polymerisation and condensation polymerisation describe the characteristics of addition polymers

using examples like PTFE, PMMA and cyanoacrylate

describe the characteristics of condensation polymers:

i. polyesters: Dacron and poly(ethylene terephthalate) (PET)

ii. polyamides: nylon, Kevlar, urea-methanal deduce the type of polymerisation reaction for a

given monomer or a pair of monomers deduce the repeating unit of a polymer obtained

from a given monomer or a pair of monomers write equations for the formation of addition and

condensation polymers explain the properties of polymers in terms of

their structures recognise the applications of polymeric

biomaterials describe the process of making biodegradable

plastics using PLA as an example relate the choice of fabrication processes to

properties of plastics and the uses of the products recognise the importance and problems of

recycling plastics

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c. Metals and alloys Strength of metallic bond Metallic crystal structures:

i. Close-packed structures as illustrated by hexagonal and cubic close-packed structures

ii. Open structure as illustrated by body-centred cubic structure

Unit cells and coordination numbers of metallic structures

Difference in properties between metals and alloys

relate the strength of metallic bond to metallic

radius and the number of valence electrons per atom

understand the close-packed and open structures of metals

identify unit cell and determine the coordination number of a given metallic structure

recognise that alloys are formed by the introduction of other elements into metals

explain the differences in properties (e.g. hardness and conductivity) between metals and alloys

relate the use of alloys (e.g. steel and brass) to their properties as compared with the pure metals, from given information

d. Synthetic materials in modern ways of

living Liquid crystals Ceramics Nanomaterials

describe the chemical structure and phase

behaviour of organic liquid crystals identify the structural features of substances that

exhibit liquid-crystalline behaviour relate the uses of liquid crystals to their properties understand that ceramic materials come in a

variety of chemical forms explain the high melting point, electrical and

thermal insulating properties of ceramics in terms of their giant molecular structures

relate the uses of ceramics to their properties describe nanomaterials as organic or inorganic

materials that have building blocks, or particle sizes, between 1 and 100 nm.

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e. Green chemistry principles and concepts of green

chemistry green chemistry practices as

exemplified by the production of synthetic materials

describe relation of sustainable development and

green chemistry understand the green chemistry practices in the

production of synthetic materials including the use of less hazardous chemical synthesis and safer solvents and auxiliaries

evaluate industrial processes for production of synthetic materials using the principles of green chemistry

Suggested Learning and Teaching Activities Students are expected to develop the learning outcomes using a variety of learning experiences; some related examples are: searching for and presenting information related to structures and properties of

polymeric materials that are used as adhesives, semiconductors and drug-carriers. writing chemical equations for the formation of polymers. deducing the monomer(s) from the structure of a given polymer. performing an experiment to prepare an addition polymer e.g. polystyrene, Perspex. performing an experiment to prepare a condensation polymer e.g. nylon,

urea-methanal. searching for information or reading article about the use of Kevlar in making

bullet-proof vests. searching for information or reading article on the advantages and disadvantages of

using a biopolymer such as Biopol (polyhydroxybutanoate). discussing the impacts of the development of materials like polymers or alloys on our

society. decision making exercise on selecting best materials for making items like daily

commodities, statues, bridges, etc. searching for and presenting information about the properties and structures of

memory metals. searching for information about the discovery and applications of liquid crystals or

nanomaterials. building physical models or viewing computer models of ceramic materials and

nanomateials. preparing hexanedioic acid by catalytic oxidation of cyclohexene.

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discussing the advantages and disadvantages of using supercritical carbon dioxide and water as solvents in place of organic solvents in production processes.

searching for and presenting information related to Ziegler-Natta catalysis on the production of polyethene.

Values and Attitudes Students are expected to develop in particular, values and attitudes, as follows: to appreciate that science and technology provide us with useful products. to appreciate the versatility of synthetic materials and the limitations of their use. to appreciate that material resources are finite and the importance of recycling

processes. to appreciate the need for alternative sources of the compounds presently obtained

from the petroleum industry. to appreciate the need for considering various properties of a material when it is

selected for a particular application. to appreciate that close collaboration between chemists, physicists, and materials

scientists are required for advancements in material chemistry. to show concern for the environment and develop a sense of shared responsibility for a

sustainable development of our society. STSE Connections Students are encouraged to appreciate and to comprehend issues which reflect the interconnections of science, technology, society and the environment; some related examples are: Synthetic materials can raise the standard of living, yet many production processes can

have undesirable effects to human health and our environment. The fundamental challenge for the chemical industry is to maintain the provision of

benefits to society without overburdening or causing damage to the environment, and all this must be done at an acceptable cost.

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Topic XV Analytical Chemistry (26 hours)

Overview In the beginning of this topic, students are expected to apply their knowledge and skills acquired in previous topics of the compulsory part to decide on and carry out appropriate tests for the detection of some common chemical species. Moreover, other than the common separation methods learnt in previous topics, students should also know that liquid-liquid extraction and chromatographic methods can be used to separate a mixture of substances. Students are also expected to understand that the determination of melting point and boiling point is an important way to indicate the purity of a substance. In addition, this topic also stresses on the quantitative methods of analysis. Students should be provided with the opportunity to solve problems related to gauging quantities of substances, if feasible, in authentic situations. In this connection, investigations using gravimetric method and different types of volumetric methods involving precipitation and redox reactions are performed. On completion of this topic, students are expected to acquire skills related to quantitative chemistry, like performing calculations and describing ways to minimise possible sources of error. Modern instruments play a key role in chemical analysis nowadays. Students are expected to acquire a basic understanding of instrumental methods like colorimetry for determination of quantity of coloured substances, infrared (IR) spectroscopy for identification of functional groups and mass spectrometry for determination of molecular structures. Students should be aware of the limitations inherent in the use of conventional chemical tests in the detection of chemical species and hence appreciate the application of modern instruments in chemical analysis. However, an in-depth understanding of the principles and detailed operation procedure of the instruments are beyond the expectation at this level of study. Instead of learning a bunch of tests and analytical methods, students can select the most appropriate means to solve problems in different situations, and justify their choices. Together with hands-on investigation experience about the nature and the quantity of chemicals, students are expected to understand the important role of analytical chemistry in daily life.

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a. Detecting the presence of chemical species Detecting the presence of

calcium, copper, potassium and sodium in substances by the flame test

Application of appropriate tests for detecting the presence of i. molecules: hydrogen,

oxygen, chlorine, carbon dioxide, water, ammonia and sulphur dioxide

ii. cations: aluminium, ammonium, calcium, copper(II), iron(II), iron(III) and zinc

iii. anions: chloride, bromide, iodide, carbonate, hypochlorite and sulphite

iv. Detecting the presence of various functional groups

(C=C, −OH, −CHO, >C=O and −COOH) in carbon compounds

select appropriate tools and apparatus for

chemical tests gather empirical information using chemical tests record observations accurately and systemically decide on and carry out an appropriate chemical

test to detect the presence of a chemical species justify the conclusion about the presence of a

chemical species either orally or in a written form understand possible risks associated with

chemical tests describe how to test for the presence of carbonyl

compounds with 2,4-dinitrophenylhydrazine and Tollen’s reagent

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b. Separation and purification methods crystallisation distillation / fractional distillation liquid-liquid extraction paper, column or thin layer

chromatography

explain the principles involved in various

separation and purification methods separate and purify substances by the following

methods: i. crystallisation ii. distillation / fractional distillation iii. liquid-liquid extraction iv. chromatographic methods

determine the Rf value of substances in a chromatogram

determine melting point and boiling point of a substance

relate the purity of a substance with reference to its melting and boiling points

justify the choice of an appropriate method used for the separation of substances in a mixture

c. Quantitative methods of analysis

Gravimetric analysis Volumetric analysis

gather empirical data with appropriate

instruments and apparatus record observations and data accurately and

systemically be aware of and take necessary steps to minimise

possible sources of error perform calculations on data obtained from

primary sources to draw evidence-based conclusions

present observation, empirical data, conclusions and sources of error either orally or in a written form

justify the choice of an appropriate quantitative method for the determination of the quantity of a substance

assess possible risks associated with quantitative analysis

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d. Instrumental analytical methods principle and applications of

colorimetry identification of functional

groups of carbon compounds using IR spectroscopy

principle and applications of mass spectrometry, including simple fragmentation pattern

explain the basic principles deployed in the

instrumental analytical methods, viz. colorimetry, IR spectroscopy and mass spectrometry

measure and record data in an accurate way using a colorimeter

identify the following groups from an IR

spectrum with a given correlation table: C−H, O−H, N−H, C=C, C≡C, C=O and C≡N

identify the following groups from a mass spectrum: R+, RCO+ and C6H5CH2

+ analyse data from primary sources and draw

evidence-based conclusions analyse data obtained from secondary sources,

including textual and graphical information, and draw evidence-based conclusions

communicate information, justify and defend evidence-based conclusions in both written and oral forms

e. Contribution of analytical chemistry to

our society analysis of food and drugs environmental protection chemistry aspects of forensic

science

recognise the use of modern instrumentation for

analysis in daily life discuss the role of analytical chemistry in modern

ways of living such as gauging levels of atmospheric pollutants like CO and dioxane; and indoor air pollutants like formaldehyde

describe the role of forensic chemistry in providing legal evidence

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Devising a scheme to separate a mixture of known substances. Performing experiments to detect the presence of certain chemical species in a sample. Designing and performing an investigation to deduce the chemical nature of a sample. Performing an experiment for gravimetric determination of phosphorus content in a

sample of fertiliser. Performing an experiment for gravimetric determination of calcium content in natural

waters using oxalic acid. Performing an experiment for titrimetric analysis of chloride using silver nitrate with

chromate indicator (Mohr’s method). Performing an experiment of titrimetric analysis of amount of hypochlorite in a sample

of bleach. Determining permanganate index of chemical waste. performing experiments to detect the presence of functional groups by simple chemical

tests.

Performing an experiment to analyse a mixture by paper chromatography, column chromatography or thin layer chromatography.

Planning and performing an experiment to determine the concentration of an unknown solution using a colorimeter.

Analysing data provided in graphical forms like spectra, drawing evidence-based conclusions, and presenting them orally or in written form.

Reviewing laboratory report and presenting critical comments orally or in written form.

Discussing the importance of integrity in recording and reporting of data. Designing and making a portable alcohol breath analyser and testing its accuracy. Searching and presenting information on the principle and application of instrumental

analysis such as gas chromatography for blood alcohol content. Identifying fingerprints by iodine sublimation. Searching and presenting information related to the use of chemical methods in

forensic science. Viewing video on the use of modern chemical techniques in chemical analysis.

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to value the need for a systematic method of solving problems. to show concern for safety and accept the need for rules and regulations required in

scientific investigations. be committed to impartial and objective gathering, analysing and reporting of

information. to respect views of others and evidence-based conclusions. to appreciate the importance of knowledge and understanding of, and practices used in

analytical chemistry to our society. to show a continuing interest in and curiosity about the advancement of science.

STSE Connections


Separation and purification techniques are used both in laboratory and in daily life. The supply of clean water to people in metropolitan districts involves a number of techniques like filtration, precipitation and distillation. For travellers to rural districts, ‘safe’ drinking water can be made from water obtained from natural sources by adding iodine tincture followed by ascorbic acid.

Consumers are often encountered with various reports of food containing carcinogens, heavy metals, pesticides, herbicides, or insecticides. Analytical chemists, with the aid of suitable tools and instruments, can provide more clues to understanding of the incidence.

Chemicals of different nature can cause different threats or hazards to our environment. Analytical chemistry can provide qualitative and quantitative evidences for such cases.

Forensic science is important in terms of its role in some legal proceedings. More specifically, chemistry plays a significant role in the process of gathering evidences and providing logical and valid conclusions.

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Investigative Study

Topic XVI Investigative Study in Chemistry (18 hours)

Overview This topic aims to provide opportunity for students to design and conduct an investigation with a view to solving an authentic problem. A portion of the curriculum time is set aside for this purpose. Students are expected to make use of their knowledge and understanding of chemistry, together with generic skills (including but not limited to creativity, critical thinking, communication and problem solving) to engage in group based experimental investigative study. Through the learning process in this study, students can enhance their practical skills and develop awareness of working safe in practical work.

Learning Outcomes Students should be able to justify the appropriateness of an investigation plan put forward suggestions on ways to improve validity and reliability of a scientific

investigation use accurate terminology and appropriate reporting styles to communicate findings and

conclusions of a scientific investigation evaluate the validity of conclusions with reference to the process of investigation and the

gathered data and information demonstrate mastery in manipulative skills and skills in observation, and also a good

general bench performance show appropriate awareness of the importance of working safely in laboratory and

elsewhere

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Implementation In general, the investigative study involves the following processes: identify relevant information, define questions for study, plan first-hand investigation, choose equipment and resources, perform first-hand investigation, organise and analyse information, and draw conclusion based on available evidence.

The following is a rough estimate of the time required for different parts of the study. • Searching for and defining questions for investigation – 3 hrs • Developing an investigation plan – 4 hrs • Conducting the investigation – 4 hrs • Organizing and analysing data for a justified conclusion – 4 hrs • Presentation of findings using written reports, posters and other means – 3 hrs

Students should have some experience with and be provided with guidelines on the following aspects before conducting an investigative study. How to work together in a group to develop an investigation plan to solve a problem How to select an appropriate question for the study, e.g. brainstorming techniques How to search for relevant information from various sources How to write an investigation plan How to write a laboratory report or making a poster for presentation

The investigative study aims to provide students with learning experience in a way that each student in a group can contribute a significant amount of effort to solving problems so as to build up their ownership, while at the same time will not be overloaded with an excessive number of tasks. The investigation can be conducted in groups of 3 to 5 students. The investigation can be undertaken on completion of a relevant topic of the curriculum. For instance, an investigative study on the topic “Chemical cell” can be carried out towards the end of the SS2 and completed at the start of the SS3. In other words, students can develop their investigation plan in March to May of SS2, the investigation can be conducted at the end of SS2, and the presentation be done at the start of SS3. Alternatively, it is also possible to conduct an investigation in conjunction with the learning of the topic. With reference to the above example, it is possible to conduct and complete the investigation in SS2.

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The study should focus on authentic problems, events or issues which involve key elements like “finding out” and “gather first-hand information”. In addition, to maximise the benefit of learning from the investigation within the time allocated, teachers and students should work together closely to discuss and decide on an appropriate and feasible topic. Scope and depth of study should be adequately deliberated. Listed below are some possible topics for investigation. Variation of the amount of active ingredient in a bleach solution upon storage. Analysis of vitamin C content in citrus fruits or vegetables. Extraction of naturally occurring chemicals and testing their uses, e.g. natural pest

repellent from citrus fruit peelings. Synthesis of a photodegradable soapy detergent and investigating its characteristics. Construction and testing of a chemical cell. Construction and testing of a home-made breath analyser.

Assessment

To facilitate learning, teachers and students can discuss and agree on the following assessment criteria with due consideration of factors that may facilitate or hinder the implementation of the study in a particular school environment. Feasibility of the investigation plan (the study is a researchable one) Understanding of relevant chemistry concepts, concerns on safety Manipulative skills and general bench performance Proper data collection procedure and ways to handle possible sources of error Ability to analyse and interpret data obtained from first-hand investigation Ability to evaluate validity and reliability of the investigation process and the findings Ability to communicate and defend the findings to the teacher and peers Appropriateness in using references to back up the methods and findings Attitudes towards the investigation

A number of assessment methods like observation, questioning, oral presentation, poster presentation session and scrutiny of written products (investigation plan, reports, posters, etc.) can be used where appropriate.

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Chapter 3 Curriculum Planning 3.1 As a senior secondary science subject in science education key learning area, Chemistry builds on the junior secondary science curriculum. In other words, students’ science learning experiences in junior secondary science should be the foundation built for learning senior secondary chemistry. In this connection, this chapter describes the linkages of the knowledge, concepts, process skills and generic skills between the two levels of study. Teachers can consider the information described below as a reference for planning their school-based senior secondary chemistry curricula for their students. 3.2 It is a well known fact that students have different interests, strength and aspirations. Moreover, students have different learning styles – visual, auditory, and kinesthetic & tactile. Thus, it is desirable to organise this curriculum in a way that address the needs of a particular group of students. On the other hand, quite often some teachers prefer certain learning and teaching approaches over the others, and they believe these approaches help to elevate the efficacy, efficiency and quality of students’ learning. Thus, teachers are encouraged to organise the curriculum in different ways to ensure “fit for the purpose”. This chapter attempts to describe some ideas for teachers to deliberate on when they need to design their own chemistry school-based curriculum. Interface with Junior Secondary Science Curriculum 3.3 This curriculum builds on the CDC Syllabus for Science (Secondary 1-3) published in 1998. This curriculum starts with the topic “Planet Earth” which helps students appreciate the world is made up of chemicals, learn some basic knowledge of chemistry, acquire some fundamental practical skills and develop positive attitudes towards chemistry. Furthermore, through the study of the topic, students can consolidate their knowledge and understanding about scientific investigation and how to investigate in a scientific way acquired in their junior science courses. Unit 1 “Introducing Science” and learning experiences on scientific investigation in Science (S1-3) are relevant. 3.4 Students should develop some fundamental knowledge and understanding of chemistry through their three-year junior secondary science courses. These learning outcomes should be regarded as the “stepping stones” for senior secondary chemistry. The following table shows how relevant chemistry topics in the CDC Syllabus for Science (S1-3) are related to different topics in this curriculum.

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Science (S1-3) Chemistry (Senior Secondary)

Unit Title Topic Title 4.3 Fuels V Fossil fuels and carbon

compounds 5.1 Water purification 5.2 Further treatment of water 5.5 Dissolving 5.6 Growing crystals

I Planet earth

6.1 State of matter 6.3 Particle model for the three states

of matter

II VI

Microscopic world I Microscopic world II

7.2 Burning V Fossil fuels and carbon compounds

7.6 Balance of carbon dioxide and oxygen in nature

I Planet earth

10.1 Common acids and alkalis 10.2 Indicators for testing acids and

alkalis 10.3 Acid and corrosion

10.5 Neutralisation 10.6 Every day uses of acids, alkalis

and neutralisation

IV III

Acids and bases Metals

13.2 How to obtain metals 13.3 Properties and uses of metals 13.4 Making metals more useful 14.1 Making plastics from crude oil 14.2 Environmental problems

associated with the disposal of plastics

III XI

XIV

Metals Chemistry of carbon compounds Materials Chemistry

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Progression of Studies 3.5 To help students with different aptitudes and abilities to explore their interests in different senior secondary subjects, The report New Academic Structure for Senior Secondary Education and Higher Education – Action Plan for Investing in the Future of Hong Kong (Education and Manpower Bureau, 2005) recommends the idea “progression of studies”.

SS3

Chinese Language,English Language,

Mathematics, Liberal Studies

X1 X2 (X3)

SS2



X1 X2 (X3)

SS1



X1 X2 (X3) (X4)

Core Subjects Elective Subjects Other Learning

Experiences

X represents an elective subject, ( ) optional

In short, schools can offer a total of 4 elective subjects at SS1 level, 3 at SS2 level and 3 at SS3 level respectively for their students.

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3.6 With the suggestion mentioned above, a number of topics have been identified from this curriculum for students intended to explore their interests in science subjects. The topics identified should help to lay the foundation for learning chemistry and facilitates students to become life-long learners in science and technology. Possible arrangements of the topics suggested are described in the scheme below. Schools can deliberate on this scheme whether it can facilitate the progression of study in senior secondary chemistry.

Include the following topics in SS1 in the school-based curriculum plan.

Topic Remarks

I Planet earth

II Microscopic world I

III Metals

All subtopics are included.

IV Acids and bases

a. Introduction to acids and alkalis

b. Indicators and pH

c. Strength of acids and alkalis

d. Neutralisation and salts

Subtopics (e) and (f) can be studied at a later stage as an introduction to volumetric analysis or as a preparation for topic XV “Analytical chemistry”.

V Fossil fuels and carbon compounds

a. Hydrocarbon from fossil fuels

b. Homologous series and structural formulae

c. Alkanes and alkenes

A detailed study of naming of organic compounds, and subtopics (d) and (e) can be studied together with topic XI “Chemistry of carbon compounds”

Subtopics (e) and (f) of topic IV “Acids and bases” can be introduced at the early

stage of SS2. After that, all topics can be organised in the sequence suggested in Chapter 2. However, it is necessary to include a detailed study of naming of organic compounds, and subtopics (d) and (e) of topic V “Fossil fuels and carbon compounds” into topic XI “Chemistry of carbon compounds”.

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3.7 Considering the rapid advancement in the world of science and technology, many contemporary issues and scientific problems have to be tackled by applying science concepts and skills acquired in wider contexts. Thereby, it is more beneficial for students to gain a broad learning experience in the three disciplines. To cater for students who are more interested in learning science and those intended taking two science subjects in science education, schools are suggested to offer a broad and balanced science curriculum for students in SS1, including all the three selected parts from biology, chemistry and physics. 3.8 During SS1, students may explore their interests in science through studying the three parts and have more understanding of the different nature and requirements of the respective disciplines. They will be more able to identify their interests and strengths for choosing their specialized study in higher forms. Moreover, the broad and balanced foundation laid in the first year of study will benefit them from associating the related concepts and skills acquired in various disciplines of science for their specialised study and keeping abreast of their interests of science in wider contexts. The diagram below is an example on how schools can organise a progression of study for students who wish to have more science learning.

SS3 Chemistry Science (Bio,Phy)

or Biology or Physics

(Other Subject)

SS2 Chemistry Science (Bio,Phy)

or Biology or Physics

(Other Subject)

SS1 Chemistry Biology Physics (Other Subject)

( ) optional 3.9 Under the New Senior Secondary Academic Structure, there will be flexibility to allow students to take up the study of Chemistry at SS2. For these students, similar sequence of learning still applies. Schools may consider allocating more learning time and providing other supporting measures (e.g. bridging programmes) to these students so that they can catch up the foundation knowledge and skills as soon as possible.

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Suggested Learning and Teaching Sequences

3.10 The topics in compulsory and elective parts of the curriculum are listed in a possible learning and teaching sequence. The sequence is organised in a way that learning starts with topics with more concrete contents, and then progress onto topics that are more abstract. For instance, students are expected to start the curriculum with the topic “Planet Earth” which is designed to be a bridge between students’ junior secondary science course and their senior secondary chemistry curriculum. After that, students are expected to start learning chemistry of matters like metals, acids and bases they commonly encountered in daily life. Teachers can deliberate on and adopt the sequence suggested. However, teachers can exercise their discretion and adopt alternative sequences to enhance their unique group of students’ learning. Some possible learning and teaching sequences are listed below.

Integration of Microscopic World I and II The curriculum put forward the idea of organising the learning and teaching of the constituents of elements and compounds, and their macroscopic properties into two separate topics (i.e. Microscopic world I and II) at different years of study. The purpose of this organisation is to avoid loading students with a bunch of abstract concepts in a short period of time, in particular, at the early stage of senior secondary level. Furthermore, the organisation also aims to provide opportunity for students to revisit their learning in the previous year of study. However, some teachers may prefer to introduce the concepts related to structures and properties in one go and believe that their students can benefit from this organisation. In this connection, teachers can organise their own curriculum in a way that the topics “Microscopic world I and II” be studied together. This kind of integration can be extended to topics like “Fossil fuels and carbon compounds” and “Chemistry of carbon compounds”; and “Metals” and “Redox reactions, chemical cells and electrolysis”.

Curriculum organisation of knowledge and skills of “stoichiometry and mole” Stoichiometry deals with the quantitative aspects of chemistry and is an emphasis of senior secondary chemistry. Concepts related to stoichiometry and calculations related to mole, formula mass, empirical formula, molecular formula, molar mass, molarity and molar volume are introduced at different parts of this curriculum, and are organised in a progressive hierarchy. These practices help students to master concepts and acquire the skills to perform aforesaid calculations without being loaded with a great deal of abstract and unfamiliar information. Teachers should

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provide opportunities to facilitate students linking these concepts and mastering the skills in a systematic way, and recognise students’ achievement using formative and summative assessment.

The figure below illustrates how the concepts related to stoichiometry and calculations related to the mole are organised in this curriculum.

Avogadro's Constant

Mole

Calculations on titrations from

chemical equations

Molarity

Stoichiometry

Mass number

Isotopic masses

Relative atomic masses

Relative molecular masses and

formula masses

Empirical formulae and molecular

formulae

Percentage by mass of an element in a

compound

Molar mass

Reacting masses from chemical

equations

Molar volume of gases

Topic II Topic III Topic IV

Topic IX

Topic IIITopic III

Alternatively, it is known that some teachers prefer to complete the study on the calculations related to mole in a relative short period of time, say before the end of SS1. With this view in mind, teachers can organise the subtopic “molar volume of gases” after topic IV. This arrangement can be beneficial to some students as they can concentrate their efforts to master concepts related to mole. Nevertheless, it is unlikely that this arrangement can fit all students throughout Hong Kong.

Integration of investigative study with elective topics Teachers may encounter groups of students having strong interest in chemical analysis and intended to carry investigative study with emphasis on analytical

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chemistry, teachers can organise the learning of the elective topic “Analytical chemistry” in parallel with the Investigative Study. This organisation helps students apply their concepts of analytical chemistry to solve problems, and at the same time develop various skills expected (please refer to “Investigative study in chemistry” in Chapter 2 for details). Furthermore, teachers can also adopt a problem-based approach by posting challenging problems to students. By solving the problems through gathering information, reading critically, learning new knowledge on their own, discussion, experimentation etc., students can master knowledge and understanding required in the topic “Analytical chemistry”, and acquire relevant skills expected in the “Investigative study in chemistry”. This kind of integration can be extended to other elective topics including “Industrial chemistry” and “Materials chemistry”.

Organisation within a topic Further to the suggested integration of major topics listed above, teachers can also arrange different sequence for learning and teaching within a topic for their students. For instance, in “Microscopic world I”, learning and teaching approach can be started with the more concrete ideas related to properties of substances and then move on to the more abstract concepts of chemical bonding. Two possible sequences are outlined below.

Sequence A Sequence B

a. Atomic structure a. Atomic structure

b. Periodic Table b. Periodic Table

e. Ionic and covalent bonding d. Structures and properties of metals

c. Metallic bonding c. Metallic bonding



d. Structures and properties of metals e. Ionic and covalent bonding

g. Simple molecular substances with

non-octet structures h. Shapes of simple molecules

g. Simple molecular substances with non-octet structures

h. Shapes of simple molecules

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On the other hand, in the learning and teaching of chemistry, teachers can adopt the “application first” approach to organise the curriculum. For instance, it is possible to attain the learning objectives associated with the subtopic “Industrial Processes” in the topic XIII using two approaches. The first approach is to provide all the foundation knowledge and concepts required prior to an in-depth treatment of the prescribed industrial processes. The second approach is an application-first one, i.e. the learning and teaching is designed in a way that the industrial processes act as the central theme, while knowledge, understanding and ideas are organised along the process of learning. Two possible sequences are outlined below.

Rate Equation

Activation Energy Catalysis Industrial Processes

(Haber Process)Sequence A

Rate Equation Activation Energy

Catalysis

Industrial Processes (Haber Process)Sequence B

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Chapter 4 Learning and Teaching 4.1 The curriculum has an in-built flexibility to cater for the interests, abilities and needs of students. This flexibility also provides a means to bring about a balance between the quality and quantity of learning. Teachers should provide ample opportunities for students to engage in a variety of learning experiences, such as investigations, discussions, demonstrations, practical work, field studies, model-making, case-studies, questioning, oral reports, assignments, debates, information search and role-play. Teachers should give consideration to the range of experiences that would be most appropriate to their students. The context for learning should be made relevant to daily life, so that students will experience chemistry as interesting and important to them. 4.2 Practical work and investigations are essential components of the curriculum. They enable students to gain personal experience of science through hands-on activities, and to enhance the skills and thinking processes associated with the practice of science. Participation in these activities encourages students to bring scientific thinking to the processes of problem-solving, decision-making and evaluation of evidence. Engaging in scientific investigation enables students to gain an understanding of the nature of science and the limitations of scientific inquiry. Designing Learning Activities 4.3 Teachers should motivate students in a variety of ways such as letting them know the goals and expectations of learning, building on their successful experiences, meeting their interest and considering their emotional reactions. Learning activities are designed according to these considerations. Some examples of these activities are given below.

Discussion Questioning and discussion in the classroom promote students’ understanding, and help them develop higher order thinking skills as well as an active learning attitude. Presenting arguments help students develop skills related to extracting useful information from a variety of sources, organising and presenting ideas in a clear and logical form, and making judgements based on valid arguments. Teachers must avoid discouraging discussion in the classroom by insisting too much and too soon on an impersonal and formal scientific language. It is vital to accept relevant discussions in students’ own language during the early stages of concept learning, and to move towards precision and accuracy of scientific usage in a progressive manner.

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One of the effective ways to motivate students is to make discussion and debate relevant to their everyday life. For example, in topic XIV, the impact of the development of modern materials is an interesting subject for discussion. In addressing issues related to science, technology and society, more student-centred strategies can be adopted. For example, in topic V, environmental issues related to the use of plastics will be discussed. Teachers can start the discussion with domestic waste classification, and plastic waste collection in schools and in housing estates. In the discussion, students are free to express their opinions, and then pool the reasons of collecting plastic waste and the difficulties of putting that into practice. Lastly students can present their ideas to the whole class and receive comments from their classmates and teacher. Practical work Chemistry is a practical subject and thus practical work is essential for students to gain personal experience of science through doing and finding out. In the curriculum, designing and performing experiments are given due emphasis. Teachers should avoid giving manuals or worksheets for experiments with ready-made data tables and detailed procedures, for this kind of instructional materials provide fewer opportunities for students to learn and appreciate the process of science. With an inquiry-based approach, students are required to design all or part of the experimental procedures, to decide what data to record, and to analyse and interpret the data. Students will show more curiosity and sense of responsibility for their own experiments leading to significant gains in their basic science process skills. Moreover, experiments are better designed to “find out” rather than to “verify”. Teachers should avoid giving away the results before the practical work, and students should try to draw their own conclusions from the experimental results. The learning of scientific principles will then be consolidated.

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Other than ordinary apparatus and equipment, teachers may explore the use of microscale equipment to enhance the hands-on experience of students in practical work. With careful design, some teacher demonstration experiments can be converted to student experiments in microscale practice.

Project Learning Learning through project work, a powerful strategy to promote self-directed, self-regulated and self-reflecting learning, enables students to connect knowledge, skills and values and attitudes, and to construct knowledge through a variety of learning experiences. It serves to develop a variety of skills such as scientific problem solving, critical thinking and communication. Project work involves students in planning, collecting information and making decisions over a period of time, and those involving experimental investigations can also help develop practical skills and more importantly science process skills. Project work carried out in small groups can enhance the development of collaboration skills. Searching for and presenting information Searching for information is an important skill to be developed in the information era. Students can gather information from various sources such as books, magazines, scientific publications, newspapers, CD-ROMs and the Internet. Searching for information can cater for knowledge acquisition and informed judgements by students. The activity should not just be limited to the collecting of information, but should also include selection and categorisation, and the presentation of findings.

Experiments include designing and planning prediction of results manipulation of apparatus collection of data consideration of safety

Conclusions and interpretations include analysis of experimental results evaluation of predictions explanation for deviations from predictions

Scientific Principles include generation of patterns and rules from conclusions and interpretations

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Construction of concept maps Concept maps are visual aids to thought and discussion, and help students describe the links between important concepts. Students should be encouraged to construct concept maps, subsequently refine their concept maps in the light of teachers’ comments, peer review and self-evaluation in the course of learning.

Information Technology (IT) for Interactive Learning 4.4 IT is a valuable tool for interactive learning, which complements the strategies of learning and teaching inside and outside the classroom. Teachers should select and use IT-based resources as appropriate to facilitate students’ learning. However, an improper use of IT may distract student attention, have little or no educational value and may sometimes cause annoyance. 4.5 There are numerous and growing opportunities to use IT in science education. IT can help search, store, retrieve and present scientific information. Interactive computer-aided learning programmes can enhance active participation of students in the learning process. Computer-based laboratory devices allow students to collect and analyse data as scientists do. Simulation and modelling tools can be employed for exploratory learning. Providing Life-wide Learning Opportunities 4.6 A diversity of learning and teaching resources should be used appropriately to enhance the effectiveness of learning. Life-wide learning opportunities should be provided to widen the exposure of students to the scientific world. Examples of learning programmes serving this purpose include popular science lectures, debates and forums, field studies, museum visits, invention activities, science competitions, science projects and science exhibitions. Students with high abilities or a strong interest in science may need more challenging learning opportunities. These programmes can stretch students’ science capabilities and allow them to develop their full potential.

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Chapter 5 Assessment Aims of Assessment 5.1 Assessment is an integral part of the learning and teaching cycle. It is the practice of collecting evidence of student learning. The aims of assessment are to improve learning and teaching as well as to recognise the achievement of students. Therefore, the design of assessment should be aligned with the learning targets, the curriculum design and the learning progression. At the same time, a diversity of assessment modes should be adopted to attain the goal of assessment for learning. Internal Assessment 5.2 Internal assessment refers to the assessment practices that schools will employ as part of the learning and teaching strategies during the three years of study in chemistry. These practices should be aligned with curriculum planning, teaching progression, student abilities and the local school contexts. Internal assessment includes both formative and summative assessment practices. The information collected will help to motivate and promote student learning. The information will also help teachers to find ways of promoting more effective learning and teaching. A range of assessment practices, such as written tests, oral questioning, observation, investigative studies, practical work and assignments, should be used to promote the attainment of various learning outcomes. Moreover, values and attitudes can be assessed in school and be reflected in the student report card of the “Student Learning Profile”. Public Assessment 5.3 Public assessment of the subject Chemistry refers to the assessment measures that lead to a qualification in the subject to be offered by the Hong Kong Examinations and Assessment Authority (HKEAA). It provides information about the standards and achievement of students based on the learning outcomes listed in this Curriculum and Assessment Guide. Public assessment of Chemistry will comprise two components: a Public examination and School-based Assessment (SBA). The assessment tasks used in the public examination and the SBA will address the learning targets laid down in this curriculum, and be aligned with the learning outcomes, such that the potential of assessment can be harnessed to encourage learning and teaching in the directions intended in this curriculum framework.

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Public examination 5.4 The public examination will consist of two papers; one focuses on the Compulsory Part of the Curriculum and the other mainly on the Elective Part. Different types of items will be used to assess students’ performance in a broad range of skills and abilities. The types of items will include multiple choice questions, short questions, structured questions and essay questions. These types of questions are currently adopted in the HKCE and HKAL examinations. When the curriculum content and the learning outcomes are finalised, sample papers will be provided to schools to illustrate the format of the examination and the standards at which the questions are pitched. School-based Assessment 5.5 SBA refers to the assessment administered in schools in which a student’s performance is assessed by the student’s own teacher. The merits of adopting SBA are as follows: i. SBA helps improve the validity of public assessment, since it can cover a more

extensive range of learning outcomes, through employing a wider range of assessment practices that cannot be implemented in public examinations.

ii. SBA allows for continuous assessment of the work of students. It provides a more comprehensive picture of student performance throughout the period of study rather than their performance in a one-off examination. Since assessments are typically based on multiple observations of student’s performance, SBA can improve the reliability of the overall assessment.

5.6 Embodying the two merits above, the rationales of implementing SBA in Chemistry are: i. To assess students’ skills in the performance of practical work and their abilities in

carrying out scientific investigations. ii. To assess students’ generic skills (such as creativity, critical-thinking skills,

communication skills, problem-solving skills, collaboration skills) through the use of a wide variety of tasks adopted in the learning process.

5.7 The SBA will contribute 20% of the total weighting of the public assessment of Senior Secondary Chemistry. 5.8 The SBA of Chemistry will be divided into two main components: practical related tasks and non-practical related tasks. The former refers to the practical work characteristic of chemistry, while the latter refers to non-practical related assignments which students are asked to carry out for the learning of the subject.

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5.9 The aim of including non-practical related tasks is to broaden the scope of assessment in the SBA, and hence in the public assessment. The abilities of students in many different aspects can be duly recognised by awarding their achievements in a wide variety of tasks adopted in the learning process. The integration of curriculum, teaching and assessment will also be much enhanced. To this end, the assignments to be included in the SBA aim to cover one or more of the curriculum content areas and one or more of the aforementioned generic skills, which are embodied in the learning targets and learning outcomes set out in the curriculum. Examples of assignments that can be used for assessment are:

Critically read, analyse and report the contribution of chemistry towards the understanding of the material world.

Design a poster or pamphlet with a view to persuade people to follow the principles of green chemistry.

Write a report to present the scientific knowledge and concepts acquired after a visit to an industrial plant.

Develop a multimedia artifact to illustrate the synthesis of polymers. 5.10 It should be noted that SBA is not an “add-on” element in the curriculum. The modes of SBA thus selected above are normal in-class and out-of-class activities suggested in the curriculum. The requirement and implementation of the SBA will take into consideration the wide range of abilities of students and will avoid unduly increasing the workload of both teachers and students. Detailed information on the requirements and implementation of the SBA and samples of assessment tasks will be provided to teachers in due course. Standards-referenced Approach 5.11 In the public assessment, a standards-referenced approach will be adopted for grading and reporting student performance. The purpose of this approach is to recognise the learning outcomes that the students have attained in the subject at the end of the 3-year senior secondary education. Each student’s performance will be matched against a set of performance standards, rather than compared to the performance of other students. Standards-referenced Approach makes the implicit standards explicit by providing specific indication of individual student’s performance. Descriptors will be provided for the set of standards at a later stage.

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Chapter 6 Effective Use of Learning and Teaching Resources

6.1 A subject curriculum and assessment guide will be published to support learning and teaching. The Guide will provide stakeholders with information on the rationale, aims, curriculum framework, learning and teaching strategies and assessment. In addition, it is anticipated that quality textbooks and related learning and teaching materials, aligned with the rationale and the recommendations of the curriculum, will be available on the market. 6.2 Resource materials that facilitate learning will be developed by the Education and Manpower Bureau (EMB) to support the implementation of this curriculum. Tertiary institutions and professional organisations will be invited to contribute to the development of resource materials. Existing resource materials, such as “Inquiry-based Chemistry Experiments”, “Chemistry Animations”, “Reactions of Metals”, “Exemplars of Learning Activities”, “Resource Book for Sixth-form Practical Chemistry”, published by EMB and various working partners will be updated to meet with the latest curriculum development. Furthermore, schools are encouraged to develop their own learning and teaching materials to meet the needs of their students as necessary. Schools are also advised to adopt a wide variety of suitable learning resources such as school-based curriculum projects, useful information from the Internet, the media, relevant learning packages and educational software. Last but not the least, experiences from various collaborative research and development projects such as “Informed Decisions in Science Education”, “Assessment for Learning in Science”, “Infusing Process and Thinking Skills into Science lessons” and “Collaborative Development of Assessment Tasks and Assessment Criteria to Enhance Learning and Teaching in Science Curricula” are good sources of information for teachers.

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Chapter 7 Supporting Measures 7.1 To facilitate the implementation of the curriculum, professional development programmes will be organised for chemistry teachers. Listed below are the major domains of the professional development programmes to be provided. Understanding the rationale and the implementation of the Chemistry Curriculum; Sharing of learning and teaching strategies and good practices; Latest development in the field of chemistry (science update programmes); Curriculum management and leadership (curriculum leadership courses); and Internal assessment, School-based Assessment and Standards-referenced Assessment.

7.2 In addition, teacher networks and learning communities will be formed to facilitate reflection and discussion on various aspects related to the curriculum. Further information on support materials can be obtained from the CDI homepage: http://www.emb.gov.hk/cd.

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