ial chemistry getting started issue 1

7/22/2019 IAL Chemistry Getting Started Issue 1

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INTERNATIONALADVANCED LEVEL

Chemistry

Getting StartedPearson Edexcel International Advanced Subsidiary in Chemistry (XCH01)

Pearson Edexcel International Advanced Level in Chemistry (YCH01)

For first teaching in September 2013

First examination January 2014


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INTERNATIONALADVANCED LEVEL

Chemistry

GETTING STARTEDPearson Edexcel International Advanced Subsidiary in Chemistry (XCH01)

Pearson Edexcel International Advanced Level in Chemistry (YCH01)

For first teaching in September 2013First examinations January 2014


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Reerences to third-party material made in this guide are made in good aith. We donot endorse, approve or accept responsibility or the content o materials, which may besubject to change, or any opinions expressed therein. (Material may include textbooks,

journals, magazines and other publications and websites.)

ISBN 9781446907122All the material in this publication is copyright Pearson Education Limited 2013

Pearson Education Limited is one o the UKs largest awarding organisations, offeringacademic and vocational qualifications and testing to schools, colleges, employers andother places o learning, both in the UK and internationally. Qualifications offeredinclude GCSE, AS and A Level, NVQ and our BTEC suite o vocational qualifications,ranging rom Entry Level to BTEC Higher National Diplomas. Pearson Education Limitedadministers Edexcel GCE examinations.

Through initiatives such as onscreen marking and administration, Pearson is leading theway in using technology to modernise educational assessment, and to support teachersand learners.

This guide is Issue 1. We will inorm centres o any changes tothis issue. The latest issue can be ound on the Edexcel website:www.edexcel.com/ial
http://www.edexcel.com/ialhttp://www.edexcel.com/ial


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1

Contents

Getting Started Pearson Edexcel International Advanced Level in Chemistry Issue 1 September 2013 Pearson Education Limited 2013

A Getting started or teachers 2

Introduction 2

Overviews 3

Course overviews 3

Unit overviews 5

The Specification 7

FAQs 7

Course Planners 8

Context Studies 12

Microscale Chemistry 16

Resources 24

B Getting started or students 25

Student Guide 25

Glossary 28


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Getting Started Pearson Edexcel International Advanced Level in Chemistry Issue 1 September 2013 Pearson Education Limited 2013

2

A Getting started or teachers

Introduction

This Getting Startedbook will give you an overview o the International AdvancedLevel (IAL) in Chemistry course and what it means or you and your students.The guidance in this book is intended to help you plan the course in outline andto give you urther insight into the principles behind the content to help you andyour students succeed in the course.

Key principles

The specification has been developed with the ollowing key principles:

A focus on choice

You can choose the contexts and practicals you use, allowing you to tailor thespecification to the needs o your students.

A motivating specification

This specification enables motivating, contemporary contexts to be included in theteaching and learning programme.

A practical specification

This specification contains practical activities embedded within each unit, to

reflect the nature o chemistry.

Assessment overview

AS units

Unit 1: The Core Principleso Chemistry

Unit 2: Application o CorePrinciples o Chemistry

Unit 3: Chemistry LaboratorySkills I Alternative

External assessment: writtenexamination paper (90 mins)



A2 units

Unit 4: General Principles oChemistry I Rates, Equilibria andFurther Organic Chemistry

Unit 5: General Principles oChemistry II Transition metalsand Organic Nitrogen Chemistry

Unit 6: Chemistry LaboratorySkills II Alternative





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Getting started for teachers A

3Getting Started Pearson Edexcel International Advanced Level in Chemistry Issue 1 September 2013 Pearson Education Limited 2013

Overviews

This section provides, at a glance, overviews o the course to help you seewhat you will need to teach. The unit overviews give a general summary o theexamined units.

Course overviews

This section provides, at a glance, overviews o the course to help you see whatyou will need to teach.

Chemistry contexts

The course can be approached through the contexts shown in the diagram.

Human Health

and Activities

Chemical

products

development

Green

Chemistry

Green

Chemistry

Chemistry

contexts

Quality

Methods

Interpretation

New

applications

Informatics

Energy

Chemical analysis

Yield and

atom economy

Combinational

theoryReaction

conditions

Product

application

Separation techniques

Sampling

Chemicaldetection Modelling Waste

management

Pollution

Environment

Sustainability

Medicinesand health

Food

Leisure

and sport

activities

Composition

and Analysis

Research


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A Getting started for teachers

4 Getting Started Pearson Edexcel International Advanced Level in Chemistry Issue 1 September 2013 Pearson Education Limited 2013

Chemistry concepts

This diagram identifies the undamental concepts in chemistry that students will

learn on this course. These concepts build on those studied in GCSE/InternationalGCSE chemistry courses and provide a firm oundation or urther study.

Fundamental

Chemistry

concepts

The mole,

formulae and

equationsSpectroscopy

and

chromatography

Chemical synthesis

and analysis

Equilibria and

acid-base redox

Organic chemistry

and mechanisms

Entropy Kinetics

Energetics

The periodic

table

Bonding

and

polarity

Atomic and

molecular

structure


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Unit overviews

The unit overviews give a summary o the content o each unit so that you can

organise your teaching effectively.

Unit 1 The Core Principles o Chemistry

Topics Suggested contexts

Formulae, equations and amounts o substance

Energetics

Atomic structure and the periodic table

Bonding

Introductory organic chemistry alkanes and alkenes

Biological systems

Climate change

Pollution

Fuels

Atom economy

Analytical techniques

Unit 2 Application o Core Principles o Chemistry


Shapes o molecules and ions

Intermediate bonding and bond polarity

Intermolecular orces

Redox

The periodic table groups 2 and 7

Kinetics

Chemical equilibria

Organic chemistry alcohols andhalogenoalkanes

Mechanisms

Mass spectra and IR

Green chemistry

Climate change

Sustainability

Food processing

Pharmaceutical industry

Nanotechnology

Inormatics

New uses o chemicals

Unit 3 Chemistry Laboratory Skills I Alternative

Students are expected to develop experimental skills, and a knowledge and understanding o the necessarytechniques, by carrying out a range o practicals while they study Units 1 and 2.

This unit will assess students knowledge and understanding o practical procedures and techniques that theydevelop.

Unit 4 General Principles o Chemistry I Rates, Equilibria and Further Organic Chemistry


How ast? rates

How ar? entropy

Equilibria

Application o rates and equilibrium

Acid/base equilibria

Further organic chemistry chirality,carbonyl compounds, carboxylic acids

and their derivatives

Spectroscopy and chromatography

Biological systems

Food

Yields and atom economy

Manuacturing

Quality control


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Unit 5 General Principles o Chemistry II Transition Metals and Organic Nitrogen Chemistry


Redox and the chemistry o the transition metals

Organic chemistry arenes, nitrogen compounds and synthesis

Fuel cells

Catalysts

Pharmaceutical industry

New applications

Unit 6 Chemistry Laboratory Skills II Alternative

Students are expected to develop experimental skills, and a knowledge and understanding o the necessarytechniques, by carrying out a range o practicals while they study Units 4 and 5.

This unit will assess students knowledge and understanding o practical procedures and techniques that theydevelop.


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The Specification

This section outlines the aspects o the specification and assessment and theaspects that have been removed, or both current Edexcel Nuffield centres andcurrent Edexcel centres.

FAQs

What is the difference between the International Advanced Level (IAL)specification and the current GCE specification?

The IAL specification is made up o 6 units which are examined by externallymarked written papers while the current 2008 GCE specification is made up o6 units, 2 o which are internally assessed coursework/practicals.

Also, the IAL examinations are available in January and June while the GCEexaminations are available in June only.

Another difference is that IALs are regulated by Pearson, thereore the award isIAL while GCEs are regulated by Oqual and the award is GCE.

Which award will a student receive if he/she completes written papersfor the AS course and completes a coursework/practical assessment in theA2 course?

The student will be awarded an IAL.

Are there any content or structural changes in the IAL specification?

No. There are no changes to content or structure, so teachers can carry onplanning and teaching in the normal way.

If a student has already completed some GCE units, would it be possibleto combine them with IAL units to complete an IAL award?

Yes. HOWEVER, only relevant GCE units which have been banked up to and

including June 2013 can be usedin combination with IAL units or a ull IALaward. This service is available until June 2015 only.

How many times can a student re-sit a unit examination?

A student can re-sit a unit examination once i.e. each unit examination can betaken twice and the higher o the two marks will be used to calculate the overallsubject grade.


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Course Planners

This section contains two course planners or the Edexcel IAL Chemistryspecification.

Course planner 1 ollows the specification through in topic order.

Course planner 2 is an alternative route through the specification, grouped byareas o chemistry which naturally fit together at AS and A2. This may suit yourparticular teaching style.

These are only suggested course planners and do not need to be ollowed.However, they may be useul in working through the specification or the firsttime.

A ull course planner will be available on our websitewww.edexcel.com/ial

Timings

Estimated teaching time available

Unit 1 60 hours AS120 hours

To include practical assessment

Unit 2 60 hours

Unit 4 60 hours A2120 hours To include practical assessment (plus extra time i youstart teaching A2 afer summer AS exams)Unit 5 60 hours


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The ollowing tables show the suggested timings o each topic.

Course planner 1Each unit is taught separately. This allows or a modular approach to the study oIAL Chemistry.

AS Chemistry autumn term Unit 1:The Core Principles o Chemistry

Topic Time (approx hours)

1.3 Formulae, equations and amounts o substance 12

1.4 Energetics 11

1.5 Atomic structure and the periodic table 9

1.6 Bonding 9

1.7 Introductory organic chemistry 14

Total teaching time (hours) 55

AS Chemistry spring and summer terms Unit 2:Application o Core Principles o Chemistry


2.3 Shapes o molecules and ions 3

2.4 Intermediate bonding and bond polarity 2

2.5 Intermolecular orces 4

2.6 Redox 2

2.7 The periodic table groups 2 and 7 16

2.8 Kinetics 4

2.9 Chemical equilibria 2

2.10 Organic chemistry 8

2.11 Mechanisms 4

2.12 Mass spectra and IR 3

2.13 Green chemistry 5



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A2 Chemistry Autumn term Unit 4:General Principles o Chemistry I Rates, Equilibria and Further Organic Chemistry


4.3 How ast? rates 10

4.4 How ar? entropy 6

4.5 Equilibria 5

4.6 Application o rates and equilibrium 3

4.7 Acid/base equilibria 10

4.8 Further organic chemistry 12

4.9 Spectroscopy and chromatography 5


A2 Chemistry Spring and summer terms Unit 5:General Principles o Chemistry II Transition Metals and Organic Nitrogen Chemistry


5.3 Redox and the chemistry o the transition metals 19

5.4 Organic chemistry arenes, nitrogen compounds and synthesis 24



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Course planner 2

This course planner allows you to teach the AS units together, and the A2 units together. Thereore the examswould be taken in June or all units. This allows or a synoptic approach to IAL Chemistry.

AS Chemistry

Autumn term Time (approx hours)

Calculations in chemistry reacting quantities and energetics 30

Atomic structure, the periodic table and bonding 25


AS Chemistry

Spring and Summer terms Time (approx hours)

Organic chemistry and analytical techniques 27

Inorganic chemistry 17

Kinetics and Equilibria 8


A2 Chemistry

Autumn term Time (approx hours)Why do chemical reactions happen? entropy and equilibria 24

Rates 12

Redox and the chemistry o the transition metals (part 1) 13


A2 Chemistry

Spring and Summer terms Time (approx hours)

Redox and the chemistry o the transition metals (part 2) 6

Further organic chemistry 36



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Context Studies

These context studies have been designed to introduce some o the contemporarycontexts that can be taught with the new Edexcel IAL Chemistry. They givebackground inormation on the context and where to look or urther inormation.Although aimed at teachers some o the context studies can be given to students,as part o the lesson, homework or background reading. The context studies havebeen designated as either AS or A2 and are mapped to areas o the specificationwhere appropriate.

Summaries o the context studies are given here. Full versions o these studies willbe available on our website: www.edexcel.com/ial

AS studies

The atmosphere

This context study looks at the different regionso the Earths atmosphere, giving basic detailsabout them. It then looks at the greenhousegases that are constantly in the news.Explaining their natural and anthropogenicsources, their chemistry and effects on the

atmosphere.

The Earths atmosphere, as seen rom space


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Green Chemistry

This context study looks at what can be doneby the scientific community to reduce theamount o greenhouses gases and pollutionthat we create. It covers the concept o carbonneutrality and ideas such as carbon capture,biouels, catalysts and atom economy, to ensurethat our carbon ootprint is reduced. Ideasabout how to reduce the amount o waste weproduce are also included.

Fuel Cells

This context study looks at what can be doneby the scientific community to reduce theamount o greenhouses gases and pollutionthat we create. It covers the concept o carbonneutrality and ideas such as carbon capture,biouels, catalysts and atom economy, to ensurethat our carbon ootprint is reduced. Ideas

about how to reduce the amount o waste weproduce are also included.

Daimler Chrysler NECar (New Electric Car),one o the earliest uel cell powered

cars developed


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AS & A2 studies

The Pharmaceutical Industry

The AS context study looks at how basicconcepts o chemistry are applied by thepharmaceutical industry in the preparation ovarious medicines. It will cover the use o massspectrometers, the use o new substances suchas carbon nanotubes and why solvents are anessential part o this industry.

The A2 context study looks at how importantorganic synthesis, stereo-specific drugsand combinatorial chemistry are to thepharmaceutical industry.


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Analysis of Chemicals

The AS context study covers the analysis ochemicals by different methods such as massspectrometry and inrared spectrometry.These methods are used in various applications,such as dating o rocks, analysis o the solarwind and the pharmaceutical industry. Detailedexplanations and examples o spectra areincluded. The A2 context study includesinormation on UV spectroscopy, NMR and alsogas chromatograph

A2 study

Supramolecular Chemistry

This is the chemistry o molecular assembliesand the intermolecular bonds and this contextstudy provides an introduction to this area.It describes its origins and why it is useul.Supramolecular chemistry is one o the mainstrands o nanotechnology and has manyapplications. One o theses is the possibleconstruction o molecular machines, whichis discussed in this study. This is a synopticcontext in chemistry and draws on many areaso the IAL.

HPLC apparatus (on the right) linked to a massspectrometer (on the lef)

An example o a supramolecule


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Microscale Chemistry

Introduction

This section gives inormation on where microscale chemistry practicals can beused within the specification.

Microscale chemistry experiments can be a very useul way o carrying outchemistry practicals. The experiments use ewer materials so the saety hazardsare ofen reduced, due to the smaller volumes o reactants and the use o plasticapparatus, rather than glassware. Fume cupboards are not needed as ofen whencarrying out microscale chemistry experiments, as due to the small volumes oreactants, small volumes o products are produced. It is recommended that a risk

analysis is carried out or all chemistry practicals. Students carrying out microscaleexperiments still improve their practical skills in the same way as with any otherchemistry practical, however it is recommended that students should haveexperience o traditional practical apparatus, as well as microscale apparatus.

Microscience is supported by many prestigious organizations. One o these is theRoyal Society o Chemistry. This section includes a statement rom the RSC withtheir view on the importance o microscale chemistry.

The Royal Society of Chemistry

The RSC is the largest organisation in Europe or advancing the chemical sciences.Supported by a network o 45,000 members worldwide and an internationallyacclaimed publishing business, our activities span education and training,conerences and science policy, and the promotion o the chemical sciences to thepublic.

Microscale chemistry is chemistry carried out on a reduced scale using smallquantities o chemicals and ofen (but not always) simple equipment. In the USAthe term smallscale chemistry is ofen preerred, especially at secondary level.There, the term microscale is normally used or organic experiments done inspecialised glassware.

Microscale experiments have several advantages: the small quantities o chemicals and simple equipment reduces material costs;

the disposal o chemicals afer the experiment is easier;

saety hazards are ofen reduced and many experiments can be done quickly;

requently, plastic apparatus can be used rather than glassware so breakages areminimized.


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Microscale chemistry is not just about doing conventional experiments on areduced scale. Ofen experiments can be done in ways such as precipitation

reactions in drops o liquid. Chemical reactions ofen proceed in small volumes osolution rather than the much larger volumes in test-tubes and beakers, and it isofen possible to make observations at microscale that are not possible at normalscale. Such experiments will teach students the importance o careul observation a skill that is vitally important in any scientific endeavour. By minimizinghazards, microscale chemistry opens up the possibility o using chemicals that aretoo hazardous to contemplate on a larger scale, increasing students experienceo practical chemistry. In general, by minimizing waste, microscale chemistryencourages responsible use o chemicals, very much a current environmentalconcern.

Sometimes experiments may be used to complement existing methods byallowing students to perorm the microscale experiments either alongside existingmethods at appropriate points in the course or as quick but useul revisionexercises at the end o the topic.

Because many o the experiments are novel and unusual, many students (andsome teachers) may take time to get used to some o the techniques. For example,using a plastic pipette requires a steady hand and the application o the correctamount o pressure to the bulb. Nevertheless i a mistake is made the dropsmay be quickly mopped up with a tissue and very little chemical will have beenwasted or time lost. With practice students should find the techniques are easy

to use. The emphasis on microscale practicals is on maximizing the opportunitiesor careul observation and interpretation. Thereore, the practical parts o theseexperiments are ofen over very quickly (in only a ew minutes) in contrast totraditional experiments which might last a whole lesson. However, this is not tosay that experimental technique is unimportant.


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Microscale chemistry practicals or use in Edexcel AS Chemistry

Practical Description LinkUsing observations ochemical changes towrite equations.

Pairs o reagents are mixed and the changes occurring are observed andrecorded. Examples could include the reactions between

a dilute hydrochloric acid and calcium carbonate

b barium chloride solution and sodium sulate solution

c copper(II) sulate solution and zinc

d dilute suluric acid and magnesium.

Both ull and ionic equations, including state symbols, are written or eachreaction.

1.3k

Using precipitates to

work out chemicalequations.

The stoichiometry o two reactions are worked out rom the heights o the

precipitates ormed and finding the optimum concentration ratio rom agraph o molar ratio o reactants against height o precipitate.

Two suitable reactions are between solutions o

a potassium chromate and barium chloride

b lead nitrate and potassium iodide.

1.3b

Experiment to find therelative atomic mass omagnesium.

Known masses o magnesium ribbon are reacted with hydrochloric acidand the hydrogen produced is collected by displacement over water and itsvolume measured.

1.3

Carrying out acid-basetitrations using the

results to calculateconcentrations osolutions and molarmasses.

Using microtitration apparatus, a standard solution o a dilute acid (eg HCl)is titrated against a solution o an unknown base (eg Na2CO3) using an

appropriate indicator.From the results o the titration the molar concentration o the solutiono the base is calculated. This may then be combined with the knownconcentration o the base in g dm-3to give the molar mass o the base.

1.3d

1.3c

Confirming theequation or thereaction betweenlithium and water.

An investigation toallow a student tomanipulate apparatus,

make measurementsand recordings and tointerpret and evaluatethe results.

A known mass o lithium is reacted with excess water. The volume ohydrogen gas produced is measured.

The amounts o lithium and hydrogen are calculated rom the results andused to confirm the balanced equation or the reaction.

The investigation may be varied by titrating the lithium hydroxide solutionproduced against standard hydrochloric acid and using the results to

calculate the relative atomic mass o lithium.

1.3b

1.3i

What is the enthalpychange or the reactionbetween an acid and abase?

The reactions between strong acids (eg HCl, HNO3) and a strong alkali(NaOH) are investigated by measuring the temperature change whenknown volumes o solutions o known concentration are mixed.

The results may be used to calculate the enthalpy o neutralisation ordifferent combinations o acid and base. These may be compared andrelated to the equation

H+(aq) + OH(aq) H2O(l)

1.4a

1.4d-


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Practical Description Link

Thermochemistryinvestigation. Anexperiment to find theenthalpy change or thethermal decompositiono calcium carbonate.

It is not possible to directly measure the enthalpy change or the thermaldecomposition o calcium carbonate:

CaCO3(s) CaO(s) + CO2(g)

The enthalpy change may be calculated using Hesss Law rom the enthalpychanges o the reactions between calcium carbonate and calcium oxidewith hydrochloric acid.

The experiment allows students to make and record observations thento interpret the results. Since the procedure is experimentally flawedstudents may use the opportunity to evaluate the method and to suggestimprovements.

1.4e

1.4fiii

How can we distinguish

between alkanes andalkenes?

Tests are carried out on a liquid alkane and a liquid alkene.

The results are compared and the differences between a saturated and anunsaturated hydrocarbon are described.

1.7.2e

1.7.3

What is the trend inreactivity o the group2 elements?

The metals magnesium and calcium are added to water and the changesobserved and recorded.

Equations are written or the reactions occurring.

1.3b

2.7.1b

Investigating somegroup 2 compounds.

Group 2 compounds are investigated by adding them to other reagents andby orming them as precipitates. Examples may include

a calcium oxide and water

b magnesium oxide and dilute suluric acid

c magnesium hydroxide and hydrochloric acid

d barium chloride solution and sodium sulate solution

e magnesium sulate solution and sodium hydroxide solution.

2.7.1c2.7.1d

How can we distinguishbetween the halide ionsCl, Brand I?

Solutions o the halide ions are distinguished by their reactions with silvernitrate solution ollowed by the reactions o the silver halides with aqueousammonia.

2.7.2d

The displacementreactions o the group 7elements.

Solutions o the halogens (Cl2, Br2, I2) are added to solutions o thepotassium halides. Any displacement reactions are observed. Ionic hal-equations are written or the reactions and they are explained as redoxchanges.

2.6.1a

2.7.2d

Reaction kinetics.

The actors that affectthe rate o a reaction.

The actors that affect reaction rate are changed and the effect o the

change on the rate o reaction is observed eg particle size o CaCO3in itsreaction with HCl; the concentration o HCl in its reaction with CaCO3; theeffect o a catalyst on the decomposition o H 2O2.

2.8.1a

2.8.1

Investigating a chemicalequilibrium.

The effect o changing the concentration o chloride ions and o addingwater to the equilibrium

[Co(H2O)6](aq) + 4Cl(aq) [CoCl42](aq) + 6H2O(l)

is investigated by observing the colour changes that occur.

1.3b

1.3i


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Reactions o alcohols. Tests are carried out on a number o simple alcohols on a microscale egmethanol, ethanol, propan-1-ol, propan-2-ol. Observations are recordedand equations written or the reactions.

The tests may include the combustion o alcohols and their reactions withsodium and PCl5.

2.9.1c

How can we distinguishbetween different typeso alcohols?

Primary, secondary and tertiary alcohols are warmed with potassiumdichromate(VI) solution acidified with dilute suluric acid. I oxidationoccurs there is a colour change rom orange to green.

Alcohols tested may include methanol, ethanol, propan-1-ol, propan-2-oland 2-methylpropan-2-ol.

2.10.1c


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Microscale chemistry practicals or use in Edexcel A2 Chemistry

Practical Description LinkThe kinetics o thereaction betweenmagnesium andhydrochloric acid.

The time taken or pieces o magnesium ribbon to dissolve in a fixedvolume o hydrochloric acid o various concentrations is determined. Therate data obtained may be used to calculate the rate o the reaction as theconcentration o HCl changes.

4.3b

4.3c

The kinetics o thereaction betweensodium thiosulate andhydrochloric acid.

The time taken or a precipitate o sulur to appear when sodiumthiosulate solution reacts with hydrochloric acid is measured. Theconcentrations o the two solutions may be changed. The rate dataobtained may be used to calculate the rate o the reaction as theconcentrations o the reagents change.

4.3b4.3c

Entropy.

Carry out simpleexperiments andexplain the observedchanges in terms odisorder and enthalpychanges.

Carry out simple experiments then suggest explanations or the

observations in terms o disorder and enthalpy change. Changes mayinclude

a solids dissolving in water both exothermically and endothermically

b the evolution o a gas when a dilute acid is added to a solid

c combustion processes that leave solid product

d mixing solids that react endothermically.

4.4

4.4g

Measuring anequilibrium constant.

Measured volumes o solutions o Ag+(aq) and Fe2+(aq) o knownconcentrations are mixed and lef to reach equilibrium.

Fe2+(aq) + Ag+(aq) Fe3+(aq) + Ag(s)

A sample o the equilibrium mixture is titrated with potassium thiocyanate

solution. From the results o the titration and the volumes and initialconcentrations o the reagents a value o the equilibrium constant may becalculated.

4.5d

Effect o temperatureon an equilibrium.

A mixture o NO2and N2Ois captured in a pipette and subjected tochanges in temperature.

2NO2 N2O4

The colour change in the pipette is observed and explained in terms othe effect o temperature on the equilibrium constant and equilibriumcomposition.

4.6a

Measuring pH. The pH o a number o different solutions is measured. Examples may

includea equimolar solutions o strong and weak acids and bases

b solutions o the same acid at increasing dilution

c the change in pH as an alkai is added to an acid.

From the readings, conclusions may be drawn concerning the way in whichpH varies with concentration, the effect o adding acid and alkali to a buffersolution and the change in pH as an alkali is added to an acid.

4.7

4.7i4.7k


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Reactions o aldehydesand ketones.

On a microscale a number o aldehydes and ketones (eg ethanal, propanal,propanone) are tested with reagents including

a Fehlings(or Benedicts) solution

b Tollens reagent

c acidified potassium dichromate(VI)

d 2, 4 -dinitrophenylhydrazine

e iodine in alkali.

4.8.2c

The iodoorm reaction. On a microscale a number o carbonyl compounds are tested with analkaline solution o iodine. Those giving a pale yellow precipitate are notedand a conclusion made about the structural requirement or a carbonylcompound or it to give a positive iodoorm reaction.

Carbonyl compounds appropriate or use in this test are ethanal, propanal,propanone, butanone, pentan-2-one.

4.8.2c

Reactions o carboxylicacids.

Ethanoic acid is used as a typical carboxylic acid to react with:

a sodium carbonate solution

b phosphorus(V) chloride

c an alcohol in the presence o concentrated suluric acid.

Observations are recorded and equations written or the reactions.

4.8.3d

The preparation o anester, ethyl benzoate.

On a microscale, a mixture o ethanol, benzoic acid and concentratedsuluric acid is warmed in a water bath. The characteristic smell o an ester

is detected in the reaction mixture afer warming.

4.8.3d

Redox titrations. Carry out titrations, using microscale apparatus, using the reagents

a potassium manganate(VII)

b sodium thiosulate.

5.3.1h5.3.1i

Complex ions otransition metals.

Aqueous solutions o complex ions o transition metals are made on amicroscale. Changes are observed and explained in terms o complex ionormation. Complex ions that may be ormed include

a [Cu(H2O)6]2+by dissolving a copper(II) salt in water

b [Cu(NH3)4(H2O)2]2+by adding excess aqueous ammonia toa solution o a Cu(II) salt

c [CuCl4]2-by adding a solution o a copper(II) salt toconcentrated hydrochloric acid

d [Zn(NH3)6]2+by adding excess aqueous ammonia to a solution o azinc(II) salt

e [Cr(NH3)6]3+ by adding excess aqueous ammonia toa solution o a chromium(III) salt

5.3.2e5.3.25.3.2g


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The reactions otransition metal ionswith aqueous sodiumhydroxide and aqueousammonia.

On a microscale, aqueous sodium hydroxide and aqueous ammonia areadded drop-by-drop, until in excess, to aqueous solutions o transitionmetal ions.

Observations including precipitate ormation and, or some transitionmetals, the dissolving o the precipitate in excess reagent, are recorded.The reactions are interpreted by writing equations or the ormationo hydroxide precipitates, amphoteric behaviour and ligand exchangereactions.

5.3.2j5.3.2k

Reactions o primaryamines.

On a microscale, primary amines (eg butylamine, phenylamine) areexamined and reacted with a number o reagents.

5.4.2b

The microscale

synthesis o azo dyes.

A diazotisation o an aromatic amine is ollowed by a coupling reaction to

orm a dye.

5.4.2d

Organic synthesis. A number o organic compounds may be prepared on a microscale usingsome o the range o techniques listed in the specification.

5.4.3


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Resources

Microscale practical guidance

Teacher and student worksheets or microscale activities are available rom theollowing sources:

John Skinner Microscale Chemistry(The Royal Society o Chemistry, 1997)

ISBN 1-870343-49-2

LS15: Microscale Organic Chemistry(CLEAPSS, 01/96)

Available to CLEAPSS members on their website www.cleapss.org.uk

Microchem worksheets(Edulab, S005/B) or A-level Chemistry (or Edexcel/OCR/AQA specifications)

A CD ROM containing more inormation and examples o microscale chemistrypracticals being carried out by students is available rom Edu-Lab.

Equipment

Microscience equipment and materials are readily available rom all the majordistributors o science equipment.

For any urther assistance, please contact:

EDU-LABKaroo CloseBexwell Business ParkBexwellNorolk PE38 9GA

Telephone: 01366 385777

Websites

www.rsc.org The Royal Society o Chemistry

www.chemistryteachers.org

www.nuffieldcurriculumcentre.org Nuffield Curriculum Centre (or teachersand technicians)
http://www.cleapss.org.uk/http://www.rsc.org/http://www.chemistryteachers.org/http://www.nuffieldcurriculumcentre.org/http://www.nuffieldcurriculumcentre.org/http://www.chemistryteachers.org/http://www.rsc.org/http://www.cleapss.org.uk/


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B Getting started or students

Student Guide

Why Study Edexcel IAL Chemistry?

This course will try to give you the skills and understanding to make decisionsabout the way chemistry affects your everyday lie by applying concepts intocontemporary areas o chemistry including:

climate change

green chemistry

pharmaceuticals

chemistry research.In addition, an IAL in Chemistry allows you to develop a range o genericskills requested by both employers and universities. For instance, a successulIAL chemist will be an effective problem-solver and be able to communicateefficiently both orally and with the written word. Handling data will be a keypart o your work, allowing you to demonstrate inormation retrieval skills aswell as use o numeracy and ICT. You will build up a range o practical skills thatrequire creativity and accuracy as well as developing a firm understanding ohealth and saety issues. As chemistry is a subject in which much learning stemsrom experimental work it is likely that you will need to work effectively as part

o a group, developing team participation and leadership skills. As you becomemore skilled you will take responsibility or selecting appropriate qualitative andquantitative methods, recording your observations and findings accurately andprecisely as well as critically analysing and evaluating the methodology, results andimpact o your own and others experimental and investigative activities.

What do I need to know, or be able to do, beore taking thiscourse?

The qualification builds on the knowledge, understanding and process skills thatyou achieved in GCSE Science, Additional Science, Chemistry, their equivalent in

International GCSE, or applied science courses such as the BTEC First Certificate inApplied Science. It is expected that you should have at least the equivalent o aGCSE/International GCSE grade C in Chemistry or Additional Science, and a GCSE/International GCSE grade C in Mathematics. In chemistry you will need to be ableto communicate effectively, be able to carry out research, work independentlyand critically think about problems. Good practical skills are also important aschemistry is a very practical subject.


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B Getting started for students


What will I learn?

Edexcel IAL Chemistry gives you the opportunity to study a core o key conceptsin greater detail. Many o the ideas first covered at GCSE/International GCSEwill be revisited but with a greater emphasis on explaining rather than simplydescribing the behaviour o molecules. While studying IAL Chemistry youwill develop practical skills that include making observations, collecting data,analysing experimental results and ormulating conclusions. You will also gain anappreciation o how scientific models are developed and evolve, the applicationsand implications o science, the benefits and risks that science brings and the waysin which society uses science to make decisions.

Is this the right subject or me?

AS or A Level Chemistry is suitable i you:

have an interest in, and enjoy chemistry

want to find out about how things work in the real world

enjoy applying your mind to solving problems

want to use chemistry to progress onto urther studies in Higher Education orsupport other qualifications or enter chemistry-based employment.

How will I be assessed?

AS Level

You will complete a written exam that lasts or 90 minutes or each o Units 1and 2. The papers will contain objective questions, short answer questions andextended answer questions. For Unit 3 you will complete a written exam that lastsor 75 minutes. The practical written examination covers the content o Units 1and 2.

A Level

You will complete a written exam that lasts or 100 minutes or each o Units 4

and 5. The papers will contain objective questions, short answer questions andextended answer questions. For Unit 6 you will complete a written exam that lastsor 75 minutes. The practical written examination covers the content o Units 4and 5.

What can I do afer Ive completed the course?

Whilst many job opportunities specifically using chemistry require higherqualifications, most laboratory-based jobs benefit rom a chemistry qualification,or instance dental assistant or veterinary assistant. Many employers view success

at IAL Chemistry as a clear indication o sound academic ability.


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Getting started for students B


Many university courses have a significant proportion o chemistry content and aIAL in Chemistry rom Edexcel is excellent preparation or such urther study. UK

HE institutions currently offer over 200 courses where chemistry is the primarysubject. Ofen these courses can include an additional years study, either inindustry or at a university abroad. Some courses can include study in other relatedareas. Examples include:

chemistry with medicinal chemistry

chemistry with orensic science and toxicology

chemistry with pharmacology.

Over 500 additional courses contain a notable element o chemistry as well asallowing a degree o breadth o study. These include:

chemistry and sports science

chemistry and politics

chemistry with computer science.

In addition a number o other courses either specifically require or find it desirableto have an IAL in Chemistry. These include courses such as chemical engineering,medicine, veterinary medicine, biological sciences, environmental science,pharmacy and dentistry.

Next steps! Visit websites to find out more about careers involving IAL Chemistry :

Royal Society o Chemistry or careers, courses and industrial placementswww.rsc.org/Education/SchoolStudents/index.asp

Association o the British Pharmaceutical Industry (ABPI) careers websitewww.careers.abpi.org.uk/Pages/default.aspx

Discuss studying this subject with your chemistry or science teacher(s).

Visit your careers office to find out more about careers and Higher Education

courses that need IAL Chemistry. Visit websites to find out what courses are available at HE which includechemistry

UCAS website www.ucas.com

Specific university websites, such asBristol University School of Chemistry www.chm.bris.ac.uk orSurrey University School of Biomedical and Molecular Scienceswww.surrey.ac.uk/subjects/biosciences-medicine

Visit the Edexcel website, www.edexcel.com/ialto obtain a ull copy o the

Edexcel IAL in Chemistry specification.
http://www.rsc.org/Education/SchoolStudents/index.asphttp://www.careers.abpi.org.uk/Pages/default.aspxhttp://www.ucas.com/http://www.chm.bris.ac.uk/http://www.surrey.ac.uk/subjects/biosciences-medicinehttp://www.edexcel.com/ialhttp://www.edexcel.com/ialhttp://www.surrey.ac.uk/subjects/biosciences-medicinehttp://www.chm.bris.ac.uk/http://www.ucas.com/http://www.careers.abpi.org.uk/Pages/default.aspxhttp://www.rsc.org/Education/SchoolStudents/index.asp


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Glossary

This glossary includes inormation on the commonly used command words romthe specification and assessment materials. It also includes explanations o someo the specialist terms and new areas o the specification.

Command words

Calculate

Students are expected to show their working, unless it is a simple one-stepcalculation.

Comment critically on

This term will most likely be used when students are being stretched andchallenged. The answer must be detailed to achieve ull marks. There will also besome easier marks, accessible or the average candidate.

Compare

Students must comment on both substances being compared.

Deduce

The answer must be worked out based either on data supplied in the question or

in one or more previous answers in the question.

Define

All the words in bold in the question must be defined, with the exception indefinitions o enthalpy changes, the term enthalpy need not be defined.

Discuss

This term will be used in more open-ended questions. There will probably be moremarking points than marks, so there will be a variety o ways in which ull markscan be obtained.

Explain

The answer must contain the theoretical basis or the answer which must bepresented in a logical order.

Identify

Either the name or the ormula is acceptable.

Justify your answer

The candidate must include the theoretical basis or the answer.


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Suggest

Students are not expected to know the answer, but to be able to work it out based

on their knowledge and understanding o material in the specification.

Specialist terms

Unit 1: The Core Principles of Chemistry

1.4 Energetics

Standard conditions: these must be given. These are 1 atmosphere pressure(or equivalent unit) and a stated temperature (usually 298K).

Hreaction: the enthalpy change or the number o moles shown in the equation.

Hneutralization: reers to 1 mol o water ormed.

Hatomization: reers to 1 mol o gaseous atoms ormed rom an element in itsstandard state.

Bond energy: the energy required to break 1 mol o the bonds and so is alwaysendothermic.

1.5 Atomic structure and the periodic table

Quantum shells: these define the energy level o the electrons. All electrons

in a given quantum shell have similar, but not identical, energies and electronsin the 1st quantum shell are in the lowest energy level. A simplified view oquantum shells is that it is the region around the nucleus in which an electron isound. The 1st quantum shell or orbit is the region closest to the nucleus.

Sub-shells: the 2nd and subsequent quantum shells or orbits are divided intosub-shells. These are o slightly different energy rom each other.

Periodicity: the properties, such as density, first ionization energy and numbero valence electrons, o the elements in the periodic table recur regularly. Forexample, the first ionisation energies rise regularly and then all to a minimumat each Group 1 element.

1.6 Bonding

Dot or cross diagrams: it is not possible to tell where electrons originated,so in the diagram or the electronic structure o an ionic compound, suchas sodium chloride, the electrons can be shown as dots or crosses or anycombination o dots and crosses. The same applies to a covalent compound.Note i the question asks or the outer electrons only, cations must not beshown with zero outer electrons.

Lattice energy: this is defined as the energy change when 1 mol o an ionicsolid is ormed rom its gaseous ions infinitely ar apart. Thus lattice energies arealways exothermic.


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1.7 Introductory organic chemistry

Molecular formula: this shows the number of atoms of each element. It should

only be used when specifically required but may be used in combustion equations.

The ormulae used in other equations and as identifiers or a substance must beunambiguous.

Structural formula: this must show any bonds, thus CH3CHO would scorewhen identiying ethanal, but not i a structural ormula were required. Thestructural ormula o ethanal is shown below.

ethanal

O

H

H3CC or

O

H

CH3C

Displayed formula: this must show all the atoms separately and all the bondsjoining those atoms.

Skeletal formula: this does not use the symbols or carbon or or hydrogenatoms that are joined to a carbon atom. A carbon atom is assumed to be at theend o every straight line and it is also assumed that the number o hydrogenatoms on each carbon atom is sufficient to complete its valency. All other atomsand the bonds (single, double or triple) between them and the carbon atom atthe end o a line must be shown. The skeletal ormulae or E-but-2-ene (trans-

but-2-ene), methypropane, propanone and propanoic acid are shown below.Bond angles must not be wrong, ie the angles around a doubly bonded carbonatom must not be drawn as 90 or 180.

E-but-2-ene methylpropane propanone

O

propanoic acid

O

OH

Hazard: this is an intrinsic property o a substance. For instance some

substances are toxic, others are flammable and others can be absorbed throughthe skin.

Risk: this relates to how the hazardous substance is dealt with. For instance therisk can be reduced by using smaller quantities or taking specific precautions,such as wearing gloves or using a water bath or heating. Hazardous materialsused in small quantities with proper containment pose little risk. The risk canbe lessened by using alternative routes, or replacing a compound with a lesshazardous one.

Structural isomers: these can arise rom different carbon chain lengths(including branching), unctional groups being in different positions on the

chain or because o different unctional groups in the two isomers.


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E- and Z- nomenclature: the naming o the isomer is determined by priorities.To decide on the priority o any group or atoms, consider the atomic number o

the atom attached to the carbon o the double bond. The one with the largestvalue takes priority. I they are the same then add up the atomic numbers oall the atoms that are attached to this first atom and again the one with thelargest value takes priority. Continue doing this until there is a difference. I theatoms or groups with the lower priority are on the same side on each end o aC=C group, the isomer is called a Z-isomer (Z or zusammen or together). I onopposite sides, the isomer is called an E-isomer (E or entgegen or opposite).

Free radical: a hal-headed or fishhook arrow represents themovement o a single electron and must be shown or the mechanism or thehomolytic fission in the initiation step o a ree radical reaction.

Electrophilic and nucleophilic addition and substitution: a double-headed(curly) arrow represents the movement o a pair o electrons and must beshown when writing the mechanisms or these types o reaction. The arrowmust start rom a bond or rom an atom or anion. In the latter examples, thelone pair o electrons need not be shown but students should realise that alone pair is the source o the moving electrons. The arrow should go to an atomwhen orming an ion or towards an atom when orming a bond.

Polymers: the repeat unit must relate to the monomer, eg the repeat unit orpoly(ethene) is:

CH2CH2

and notCH2

Unit 2: Application of Core Principles of Chemistry

2.3 Shapes of molecules and ions

Drawing molecules and ions: these should be drawn with reasonably correctbond angles, eg 180 or linear molecules and 120 or trigonal planar molecules.

Three-dimensional molecules: these should be drawn with wedges and dashes,where a wedge represents a bond coming out o the paper and a dash or a

bond going behind the paper.

2.5 Intermolecular forces

Hydrogen bonds: the angle around the hydrogen atom in a hydrogen bondmust be drawn as 180 and that around the F, O or N atom involved as anangle considerably less than 180 but more than 90. Thus in solid hydrogenfluoride the molecules are arranged in a zig-zag shape.

F

F

F

HH

H


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Hydrogen halides: students should be aware that in the halogen hydrides,HCl to HI, the strongest intermolecular orce is permanent dipole/dipole

interactions.

2.6 Redox

Disproportionation: this is defined as a reaction in which an element in asingle species is simultaneously oxidised and reduced.

2.7 The periodic table groups 2 and 7

Flame tests:

Metal ion Flame colour

sodium yellow

potassium lilac

calcium yellow-red

lithium and strontium red

barium pale green

The chemical and physical properties of fluorine and astatine: these shouldbe predicted by extrapolation of the properties of the other halogens. For fluorinethe predictions may not match the facts as, for instance, the F-F bond is weaker

than the Cl-Cl bond. Other properties such as bond enthalpies between thefluorine or astatine and other elements, 1st ionisation energies, electronegativities,oxidising power and boiling temperature can be predicted with accuracy.

Precision, accuracy and reliability: students must be able to distinguishbetween these three terms. Precisionis the number o significant figures ordecimal places that can be read on an instrument such as a thermometer. Theaccuracyo a measurement is how close that measurement is to the true value.For instance a digital thermometer can have a three decimal place precisionbut be extremely inaccurate. (This would not matter or measurements otemperature change providing the inaccuracy is constant, ie is a systematic

error.) The reliabilityo an experiment depends on intrinsic errors such as heatlosses and the skill o the person perorming the experiment. Repeating anexperiment will not increase the reliability o the experiment or o the accuracyo the result i the same errors are present.

2.8 Kinetics

The reaction profile: this must show the relative energy levels o the (named)reactants and products, the transition state with the activation energy markedand the enthalpy o reaction. For a catalysed reaction, there should be twohumps with the energy level o the intermediate normally being shown at anenergy level less than that o the reactants but above that o the products. Bothactivation energies must be smaller than that or the uncatalysed reaction.


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2.11 Mechanisms

Nitric oxide, NO: students should understand that this depletes the ozone in

the upper atmosphere in a ree radical chain reaction. The nitric oxide producedby aircraf has more effect on the ozone layer than the nitric oxide produced bycars at ground level, as most o the latter is washed out o the atmosphere byrain.

2.13 Green chemistry

Atom economy: this is defined as the percentage o the atoms o the reactantsthat are converted into useul products and so not wasted. For example thereaction between ethene and bromine has a 100% atom economy, but thereaction between ethane and bromine is much lower, as hydrogen bromide

is a by-product. Another 100% atom economy process is the manuacture oethanoic acid rom methanol and carbon monoxide.

Anthropogenic climate change: this is any change in the Earths climatecaused by activities o mankind. This is different to that caused by naturalevents, such as volcanic eruptions and changes in the Suns activity or theEarths orbit around the Sun.

Carbon neutrality (of a fuel): this is when the production o carbon dioxidewhen the uel is manuactured and then burnt equals the absorption o carbondioxide when the raw material is grown. This must be in terms o individual

human lietimes and not geological time spans. This means that no uel istotally carbon neutral but its carbon ootprint can be very small (see carbonfootprint).

A carbon neutral activity: this has no net annual carbon dioxide (greenhousegas) emissions to the atmosphere.

Carbon footprint (of a fuel): this is the total mass o carbon dioxideproduced rom a uel when it is manuactured and then burnt, in units o g perkilojoule o energy released in combustion. I the uel was produced by growinguel crops such as sugar or vegetable oils, the amount o carbon dioxide thatwas absorbed in growing the raw material o the uel should be subtracted rom

this total mass o carbon.

Carbon footprint (in general): this is a measure o the amount o carbondioxide emitted through the use o ossil uels; in the case o an organization,business or enterprise, as part o their everyday operations; in the case o anindividual or household, as part o their daily lives; in a product or commodityall processes involved in its production and in reaching the market. Ofenmeasured in tonnes o carbon dioxide.


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Unit 4: General Principles of Chemistry I Rates, Equilibria and FurtherOrganic Chemistry.

4.3 How fast? rates

Rate of reaction: this is measured as the change in concentration o a reactantor product per unit time. It is the gradient at a given point o the graph oconcentration against time (or o other quantities that are proportional to theconcentration o a reactant or product, such as volume o gas evolved).

The initial rate: this is the rate at the start o the reaction.

Order of reaction: this is the sum o the powers o the concentrations o thesubstances in the experimentally determined rate equation. I it is defined asthe sum o the partial orders, then the term partial order must also be defined.

4.4 How far? entropy

Thermodynamic stability: the reactants are said to be thermodynamicallystable relative to the products i the value o Stotalor the reaction is negative.

Kinetic inertness: the reactants are said to be kinetically inert relative to theproducts i the activation energy or the reaction is high. This means that therate constant will be low.

4.5 Equilibria

Effect of change in temperature: students should understand that anincrease in temperature alters the value o Ssurroundingsand hence Stotal. Thereorethe value o the equilibrium constant will change. This will then cause theposition o equilibrium to shif to restore equality between the new value o Kand the concentration or partial pressure term.

Effect of change in pressure: students should understand that an increasein pressure will not alter the value o the equilibrium constant but may alterthe value o the concentration or partial pressure term. This will cause thecomposition o the equilibrium mixture to change as the position shifs torestore equality.

4.7 Acid/base equilibria

Buffer solution: this is a solution that does not significantly change in pH(resists a change o pH) when small amounts o H+or OHions are added.

Students should understand that this will only occur i the amounts o both othe acid/base conjugate pair are large relative to the small amounts o H+orOHions added.

4.8 Further organic chemistry

A chiral molecule: is a molecule which is non-superimposable on its mirror image.


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Transesterification: this is the reaction of an ester with either an acid or an alcoholto produce a different ester (this is nothing to do with cis and trans isomerism).

4.9 Spectroscopy and chromatography

NMR spectroscopy: students should understand that the energy o the radiorequency waves promotes some protons into a higher energy level, where theirmagnetic moments are antiparallel to the applied magnetic field.

Gas-liquid chromatography (GLC): this is a orm o chromatography wherethe stationary phase is a liquid on an inert support and the moving phase isgaseous. The gaseous phase consists o a carrier gas into which a volatile samplehas been injected.

High pressure liquid chromatography (HPLC) (also calledhigh

performance liquid chromatography): this consists o a stationary phaseand a flowing liquid phase which is orced through a column containing thestationary phase by high pressure.

Unit 5: General Principles of Chemistry II Transition Metals and OrganicNitrogen Chemistry

5.3 Redox and the chemistry of transition metals

Standard electrode potential: this is the electric potential difference (em)between the electrode in a hal-cell and a standard hydrogen electrode. Allsolutions must be at a concentration o 1moldm-3, all gases at 1 atmosphere

pressure (or equivalent in other units) and the system must be at a statedtemperature (usually 298K).

Redox titrations: during these burettes should be read to an accuracy o0.05cm3. The uncertainty o the accuracy is determined by the quality o theburette. The validity or reliability o the titre is determined by the ability o thestudent perorming the titration and making the reading.

The idea is that the larger the volume o the titre the greater is its percentageaccuracy (or the lower the percentage error).

5.4 Organic chemistry arenes, nitrogen compounds and synthesis

Condensation polymers: the repeat unit o polyesters and polyamides musthave the bond o the C=O group clearly shown.

Combinatorial chemistry: this can be illustrated by the production oproteins. Amino acids can be attached to polystyrene beads. The beads aredivided into a number o portions equal to the number o different amino acidsbeing used in the synthesis. In step one a different amino acid is attached toeach set o beads, then mixed and separated into portions. In step two thenext amino acid is added on. I 20 different amino acids are used, 202 or 400different dipeptides are produced, 203 or 8000 different tripeptides etc. At theend, a particular bead can be selected containing a laboratory made protein

with a specific peptide sequence.


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