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PEOPLEIN

SCIENCEElements and Atoms

Peter EllisAdditional material by Alastair Sandiforth

54505_Atoms_El_prelims 3/7/02 11:03 am

Pearson Education Immersive EducationEdinburgh Gate The Old MalthouseHarlow Paradise StreetEssex OxfordCM20 2JE OX1 1LDwww.peopleinscience.co.uk

© Pearson Education Limited and Immersive Education Limited 2002

Kar2ouche‚ the application © Immersive Education Limited and The University of Oxford 1998-2002

The right of Peter Ellis to be identified as the author of this work has beenasserted by him in accordance with the Copyright, Designs and Patents Actof 1988.

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic,mechanical, photocopying, (except for the photocopiable worksheets),recording or otherwise without the prior written permission of the Publishersor a licence permitting restricted copying in the United Kingdom issued by the Copyright Licensing Agency Ltd, 90 Tottenham Court Road, London,W1P 9HE.

The following pages may be photocopied for classroom use:26-28, 31-33, 36-38, 41-43, 46-48, 51-54, 57-59, 61-64

ISBN 0582 77306 7

Design concept by Raven Design,Ware, Herts and Gemini Design, Hersham, SurreyPage make-up by Gemini Design, Hersham, SurreyCover and CD label design by Immersive Education LimitedPrinted in Great Britain by George Over Limited, Rugby

The publisher’s policy is to use paper manufactured from sustainable forests.

AcknowledgmentsThe publishers wish to acknowledge Faber and Faber for the use of the poemThe Innocence of Radium by Lavinia Greenlaw, reproduced on page 59.

We would like to thank Jim Henderson, Key Curriculum Leader- Science,Maths and Design Technology,The Charter School, London, for his work asa reviewer.

The Immersive Education team are:Alex Cane;Ashfaq Khan; Ben Hanke; BorisSamson; Brian Unwin; Carl Wenczek; Carol Macintosh; Claire James; DamienRochford; David Hailey; Donna Burton–Wilcock; Hasraf Dulull; Ian Downend;Ian Roe; Ivelina McCartney; James Broad; John McDonnell; Lloyd Sutton;Mandy Schmidt; Marie-Claire Barnes; Mark Miles; Rachel Nalumoso;Sarah Storrs; Simon Beaumont; Steven Arkell; Stephen Hawkins; Steve Young.

Peter Ellis has been teaching science for 27 years and has an M.Philin Chemical Education. He served a term as Chairman of the EducationSection of the British Society for the History of Science.

Alastair Sandiforth is Head of Science at Stanborough School,Welwyn Garden City. He is also a Principal Examiner for GCSE Biologyand Assistant Principal Moderator for GCSE Science coursework.


PEOPLEIN

SCIENCEElements and Atoms

Peter EllisAdditional material by Alastair Sandiforth


4 © Pearson Education Limited and Immersive Education 2002Elements and Atoms

Contents

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Introduction 5

Using People in Science in the classroom 8

Developing thinking and literacy skills 10

Development of ideas 12

The characters 17

Matching charts 20

Themes and activities

What are elements? 24

Ideas about burning 29

Ideas about atoms 34

Atomic weights and the Periodic Table 39

Inside the atom 44

Discovering elements 49

Using radioactive materials 55

Further suggestions 60

Quick start guide to Kar2ouche® 61I

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A Introduction

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People in Science – Elements and Atoms is one of a series of six CD-ROMs each withaccompanying support materials.They are designed to help teachers deliver the Ideasand Evidence strand of Sc1 in an interesting and motivating manner, and to developstudents’ thinking and literacy skills at the same time.The series is accompanied by acompanion website at www.peopleinscience.co.uk.

Kar2ouche®

People in Science uses Kar2ouche® - an innovative software product that allows students toread and/or listen to text, and to create storyboards which describe a sequence of events,presenting arguments, debates, or factual information. Suggestions for different ways ofusing Kar2ouche® to teach science and to develop thinking and literacy skills are givenin Sections B and C (pages 8 onwards).A ‘Quick Start’ guide to using Kar2ouche® isprovided at the back of this file, and a full instruction manual can be downloaded fromthe website www.peopleinscience.co.uk.

Ideas about elements and atomsThe Elements and Atoms CD includes a selection of scientists whose stories and ideas canbe used to illustrate the development of knowledge about the nature of matter, up toand including the discovery of electrons, protons and neutrons, and the discovery ofradioactivity. Each historical character narrates a brief outline of his or her life story,and then explains their scientific ideas and the evidence for them. Modern, fictionalcharacters are also included to present arguments for and against the use of radioactivematerials in medicine.An outline of the scientific developments covered by Elements andAtoms is given in Section D (page 12), and short biographies of the characters areincluded in Section E (page 17).

Section F (page 20) provides matching charts to map the themes to:� the National Curriculum for England� the National Curriculum for Wales� the Guidelines for Scotland� Scottish Standard Grade specifications.

In addition, matching charts are available on the website for the following:� the QCA Scheme of Work for England� GCSE specifications from AQA, Edexcel and OCR.

The ThemesThe material provided on this CD can be used to cover a number of themes; eitherspecific discoveries or ideas (e.g. the phlogiston theory) or ways of doing science(e.g. the importance of evidence in the development of ideas).This pack includes7 suggested Themes, covering different aspects of ideas about elements and atoms.For each Theme there are two suggested activities (of varying difficulty), a set ofteacher’s notes, a classwork sheet and a homework sheet.The CD includes two partiallycompleted storyboards for each Theme, to help students to get started on the activities.

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The activities and storyboardsIn writing the activities we have attempted to provide a variety of tasks as well aslooking at different scientific ideas.The suggested activities vary from creatingstraightforward storyboards to describe a sequence of events, to constructing a museumexhibit or a television interview.We have provided two activities for each Theme(and three for Theme 7), with the first activity generally being easier than the second.The suitability of each activity for KS3 and KS4 pupils is indicated in the teacher’snotes. Each activity is further differentiated into Sections A, B and C. Students should allstart on section A.

A storyboard is provided for each activity (except for Activity 4.2, for which a Worddocument is provided instead).The information about each scientist can be accessed viathe text/audio window by clicking on the blue book symbol.The storyboards havesome frames already created, and prompts or questions in the comment window belowthe frame.The classwork sheets give students a brief outline of the activity andsuggestions for completing the storyboard.

The activities suggested in this Teacher’s File are intended to help teachers and studentsnew to working with Kar2ouche® – there are many other possible activities that can becarried out using the text and characters provided.A few more suggestions are given inSection H (page 60).

Kar2ouche® allows teachers to personalise various settings, determining whichcharacters, backgrounds and props students have access to. Further details on this facilitycan be found in the user manual.

The Homework SheetsA homework sheet is provided for every Theme.The sheets are intended to be ‘stand-alone’, in that they do not rely on students having completed all of the correspondingactivity, and they do not require students to have the software at home or to take homeprinted versions of their classwork activities.They are intended to consolidate ideasintroduced via the activities.

We have provided a range of questions on each homework sheet.Teachers may like to select which questions students are to answer for homeworkdepending on the ability of the class. One question on each sheet is a research questionindicated by this symbol: .

These require students to use books or the Internet. Suggested web links are given inthe Teacher’s Notes where appropriate.All weblinks can also be found on the People inScience website.



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The Teacher’s NotesThe Teacher’s Notes for each theme include the following information:� a box indicating which students the activities are suitable for.

‘All’ means that all students at that Key Stage should be capable of carrying out the activity successfully; ‘Most’ means that most students should be able to carry out the activity, but that it is not

suitable for the least able (or the least able will need considerable help); and ‘Some’indicates that the activity is suitable for more able students only, at that Key Stage.

� learning objectives� learning outcomes� an indication of any prior knowledge that students will need before starting

the activities� a list of National Curriculum statements that can be covered (or partially covered)

using the activities� a brief background summary of the scientific developments or debates covered by

the Theme� an outline of the suggested activities and the storyboards provided� a list of the characters, backgrounds and props needed (this provides a quick

reference list in case teachers wish to lock out any characters, props or backgroundsnot needed for the activities).

� suggestions for organising the lesson� answers to questions on the homework sheet.

The website www.peopleinscience.co.ukThe companion website includes:� a full user manual for Kar2ouche®, downloadable as pdf files� Frequently Asked Questions� an area where teachers can submit or download ideas or storyboards, to share

teaching ideas with other schools.� a list of weblinks suitable for students to use to answer research questions

At the time of publication, all web addresses listed in this Teacher’s File have beenchecked for their content and suitability. However, we would advise that all web links aretested before use in class, to ensure that they are still useful and appropriate.

Customer SupportKar2ouche® is easy to install and run, but if problems are encountered,call the Customer Support Line on 01865 811099.

Activity KS3 KS4

1.1 Most All

1.2 Some Most

System Requirements

• 50 mb free hard drive space • 32Mb of RAM • CD ROM Drive• Mouse • 1024 x 768 or 800 x 600

16 bit video display• Microphone and Speakers

(Kar2ouche will work without these,but users will not experience thebenefits of the software without them)

PC / Windows SystemRequirements

• 300 MHz or higher Pentiumcompatible processor

• Windows 95/98/2000/ME/XP• Microsoft DirectX 8.0 or

higher (installed automatically if notfound)

• QuickTime 5.0 or higher(installed automatically if not found)

Mac OS SystemRequirements

• Suitable for PowerMac orPowerbook

• Mac OS 8.6 or later• CarbonLib 1.1 • QuickTime 5.0 or higher

(installed automatically if not found)



B Using People in Sciencein the classroom

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The material provided on the People in Science CDs can be used in the classroom in anumber of ways.This section gives a general overview of the possibilities, with moredetailed suggestions for each Theme given in the Teacher’s Notes and via the ready-made storyboards.

Organising the lessonStudents gain most value from the kinds of activity suggested here if they are given ageneral introduction to the lesson before they start using the software, and if what theyhave learned can be summarised and shared with others during a plenary session at theend of the lesson. Specific suggestions for starting and finishing lessons are made in theTeacher’s Notes for each Theme.

Students can work alone, in pairs or even threes. For many students, working in pairsprovides encouragement, an opportunity to share ideas, and a chance to clarify ideasby discussion with a partner. For this reason, it may be better to ask students to workin pairs even if there are sufficient computers for students to be able to work alone.

StoryboardsA storyboard is a series of frames that tell a story or convey a sequence of events.They can be viewed as separate frames in sequence or animated and played as a ‘movie’.Storyboards are particularly useful in encouraging students to show their understandingand demonstrate their ability to extract and summarise key information.

Students can be asked to create:� a summary of a particular event or piece of text in a specified number of frames� a summary with speech bubbles or captions containing important quotations� a storyboard with their own commentary or a summary in their own words� presentations for the class to view� illustrations of alternative points of view, or a debate� imagined meetings between characters� a proposal for a new documentary to be presented to a board of TV executives.

While the main ideas in a storyboard are likely to be conveyed via text (either in thetext window or in speech, thought or text bubbles), students can enhance theirpresentations by adding sound effects, extra characters or props, all of which can befound on the CD. In addition, they can add their own digital images, or record the textin their own voices.

If time is limited, teachers can provide partially completed storyboards that studentsfinish in the lesson. Students can also be asked to create their own incompletestoryboards for other students to complete. Partially completed storyboards maycomprise, for example:� the first and last frames – students make the frames for the central section� storyboards that contain blank thought bubbles, blank speech bubbles

and/or blank text boxes� storyboards with questions in text boxes or in the caption window� storyboards with text in the caption window – students create the pictures� storyboards with odd frames missing� sequencing activities� a quiz – ‘who says what?’, or ‘what happens next?’

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AnimationsStudents who have access to Kar2ouche® out of class time enjoy creating animations.As with storyboards, animations enable students to demonstrate their understanding andability to extract key information. Most of the activities listed below can also be createdas still storyboards. Students may be told that they have been commissioned to create aprogramme such as:� a news programme� a documentary� a TV chat show/interview� a documentary trailer.

PublicationsTo summarise a topic, students can present their storyboards to the class using a dataprojector, interactive whiteboard, or on screen. Alternatively, they can use the printfacility to create publications in Kar2ouche®, or copy images into a word-processing ordesktop publishing program.

Possible publications for students to create include:� a newspaper front page – using Kar2ouche® to produce the pictures and the text

as a resource� storybooks, with the story below the picture in the caption window

(concentrating on structure or settings etc)� cartoon strips (or film storyboard strips)� diary entries (with photos or pictures)� letters (with pictures)� photo albums� magazine spreads.

In all of these activities students may be asked to consider audience and purpose.Teachers can stipulate this audience.

When using People in Science the possibilities are almost endless.As teachers get usedto the software and use it within their particular area of expertise, other activities willsuggest themselves.



C Developing thinking and literacy skills

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Although the focus of the activities in People in Science is for students to learn aboutscience, in particular the development of ideas and evidence over time, there are alsoample opportunities for pupils to develop their thinking skills and literacy skills.This section outlines some of the skills that can be developed.A matching chart is availableon the website, which links the suggested activities to the National Literacy Strategy.

Information-processing skillsStudents can be encouraged to:� identify key images, text, and ideas – and extract what is essential� sort the relevant from the irrelevant� organise and, where necessary, prioritise ideas� sequence events� compare and contrast their work with the work of others.

Reasoning skills Students can be encouraged to:� justify opinions using evidence� make informed choices� consider alternative perspectives or interpretations� articulate ideas.

Enquiry skillsStudents can be encouraged to:� work collaboratively to extract information from texts� consider consequences� reflect critically on written text, their own work and the work of their peers.

Creative thinking skillsStudents can be encouraged to:� offer interpretations of texts or situations� create multi-media texts� respond imaginatively to texts or situations.

Evaluation skillsStudents can be encouraged to:� engage in collaborative work and dialogue� review, modify and evaluate work produced.

CommunicationStudents can be encouraged to:� engage in group discussion� present ideas to a group� use visual aids and images to enhance communication� listen, understand and respond critically to others.

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Literacy skillsAt word level you can draw attention to key scientific words and their spelling.Students should be encouraged to look up any unfamiliar words in the glossary providedon the CD, and to compile their own lists of new words.Alternatively, lists of new wordscan be made into posters and used in a wall display.When introducing new vocabulary,encourage students to draw on analogies to known words, roots, derivations, and familiarspelling patterns.

In creating a range of storyboards, students can be encouraged to pay attention tosentence level literacy skills. In particular they should pay attention to sentencestructure and the consistent use of tenses.At a more advanced level they should beencouraged to consider the differences between written and spoken language in terms ofdegrees of formality and the techniques that speakers employ to persuade an audience totheir points of view.

Work at a text level can be varied.As far as the students’ reading skills are concernedthe activities require them to develop a range of research and study skills, includinglocating information from the given text through skimming, scanning and searchtechniques.At a more advanced level they are required to bring in information froma range of sources, and to evaluate and re-present this for a specific audience. Somestudents may need clear directions that will help them to develop these skills.

The writing demands of the activities are varied from virtual performances and debatesto newspaper reports. Students should be shown how to take effective notes, organiseideas and use evidence.

The software is particularly suitable for pair and small group work and thus forfacilitating the development of speaking and listening skills.When working in pairs,students can be given instructions to use talk as a tool for clarifying ideas by discussing,hypothesising, citing evidence and asking questions. In many of the activities students arerequired to promote, justify or defend a point of view using supporting evidence,example and illustration. During plenary sessions students will be required to listen,ask questions, comment, and possibly evaluate the presentations they have viewed.With teacher direction, students can be allocated different roles in their groups topractise different skills.The storyboarding activities allow pupils to engage in virtualrole-play, therefore developing their drama techniques in a variety of situations and inresponse to a range of stimuli.



D The development of ideasabout elements and atoms

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Reason and speculation in Ancient CivilisationsWho knows when people began to wonder about the materials in the world aroundthem? Certainly from earliest times people were able to recognise the properties anduses of various substances – flints, clay, bone, and wood. Ideas and myths about the formthat matter took developed in the early civilisations of India, China, Egypt and Babylon.By the first millennium BCE* these ideas had crossed the Mediterranean to Greece, theGreek colonies in Sicily, and also to the coast of what is now Turkey.

Greek philosophers developed the ideas that they had learnt, applying rules of logicalreasoning along with empirical observation.Thales (625 – 547 BCE) is attributed withthe first general principle – that all substances are actually water, though this idea wasknown to the Babylonians. Many interesting legends surround the life of Empedocles(490 – 430 BCE), and he is important because he is credited with the idea that matter ismade up of the four elements – Earth,Air, Fire and Water.This theory was accepted inone form or another for two thousand years and even today is a part of our language.Empedocles also showed that air has weight.

At a similar time, Democritus and his tutor Leucippus put forward the idea that matterwas made up of indivisible particles that they called ‘atoms’. Democritus had deducedthe existence of atoms but the majority of Greek philosophers,Aristotle included,preferred the idea that space was filled with a continuous material called the ‘plenum’.This theory reappears at various times in the form of the aether and even today there isthe concept of the quantum vacuum that suggests that the void between atoms is notformless and empty of activity.

Plato and his pupil,Aristotle, refined the four-element theory, adding a fifth element,the cosmos, to represent the space above the Earth.Aristotle was an expert observer asshown by his work in natural history, and he based his acceptance of the four elementson observations of the behaviour of substances and in particular the effect of combustionon burning wood.A burning log produces flame (fire), fumes of gas and vapours (air);liquids run out of it (water) and ash (earth) is left when burning is complete.

Greek ideas spread and develop in the Islamic worldGreek philosophy and culture spread around the Middle East during Aristotle’s lifetime,partly due to the conquests of Alexander the Great. In Egypt and Persia, Greek theoriesbecame mingled with the practices of craftsmen and religion to become the art ofalchemy. For the alchemist the four-element theory was central to the idea that thenoble metal, gold, could be produced by adjusting the proportions of the elementspresent in base metals such as iron and lead. In their efforts, the alchemists developedmany of the processes familiar to the modern chemist – mixing, heating, dissolving,filtering, refluxing and distilling. For example, the invention of the still is credited toMaria the Jewess in the early years of the Christian era.

* Before Common Era (BCE) is used instead of AD in non-Christian contexts.



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Muslims and ChristiansWhile Western Europe was split into small nations of warring tribes, the Arab world wasadopting Islam and spreading its culture across North Africa and the Middle East. In therich cities such as Baghdad, alchemists were respected members of the court.The alchemists, doctors and philosophers had access to the works of the Greekphilosophers and translated them into Arabic.They also had contact with the easterncivilisations of India and China and as a result made many advances, particularly inmathematics and what we now call chemistry.

In the 11th and 12th centuries there was increasing contact between Western Europeand the empires of Islam, mainly through wars of liberation and conquest. However theresult was that Arabic and Greek works filtered into the consciousness of learned peoplein Europe.The only literate people with training in logic and argument were themembers of the religious orders.They read and translated the works of Aristotle, Jabirand many others and gradually assimilated them into Christian dogma. Indeed,Aristotle’sworld-view was adopted by the Catholic Church. Not all learned men and womenaccepted all that Aristotle wrote. Roger Bacon, a 12th century Franciscan monk, sawinconsistencies in what he read and proposed experiments to test ideas, although there isno record of him carrying out controlled experiments. Nevertheless his questioning ledto trouble with the leaders of his order.

Elements and PrinciplesThe Greek idea of the four elements was extended by the Arabs and the medievalChristians to include the concept of Principles.The Principles were theoreticalsubstances that endowed solids and liquids with the properties of combustibility, lustre,and malleability. Jabir proposed two Principles – Mercury and Sulfur. Real substanceswere mixtures of these principles. Later, Christian alchemists and iatrochemists, ormedical-chemists such as Paracelsus, referred to Mercury, Sulfur and Salt as thecomponents of matter.

The concept of the Principles gave support to the idea that metals could be changedfrom one type to another, from iron or lead into silver or gold, by the appropriatemixing of substances.To achieve success the mixtures had to pass through variousprocesses which were described in symbolic and ritualistic terms.The alchemistsoperated in great secrecy, which added to their aura of mysticism.

Alchemy becomes ChemistryTowards the end of the seventeenth century science attracted the interest of a growingnumber of gentlemen. Many dabbled in alchemy, some, like Isaac Newton and RobertBoyle, more than others. Boyle became disillusioned with the symbolism and ritual ofalchemy and tried to perform controlled experiments. His book, The Sceptical Chymist,whilst written in boring and convoluted language, does contain the beginning of themodern concept of an element.With his experiments on air, Boyle came close torevealing the truth about burning. He proved that air was necessary for combustion butmissed the significance of the inrush of air when sealed tubes containing metals wereopened after heating.

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Shortly after Boyle’s lifetime the phlogiston theory of combustion proposed by JohannBecher and Georg Stahl became the accepted view of the majority of chemists.Phlogiston was just one of a number of ‘imponderable fluids’ which gave substances theirproperties. Other fluids included ‘caloric’ (heat) and the ‘electric fluid’.The phlogistontheory was successful partly because it made predictions that could be tested.A metalcalx (the ash left after a metal was burned), when heated with charcoal (thought to bealmost pure phlogiston), did produce the metal.The fact that metals gained mass onburning was either ignored or explained away. It was suggested that phlogiston musthave ‘levity’ i.e. negative weight. Newton’s laws of motion and gravity had yet to beapplied to chemistry, although accurate balances had been in use for many decades.

The air becomes a mixtureThe late eighteenth century saw air as the focus of attention in many Europeancountries, including Britain, Sweden and France. Glassware for collecting gases, andburning glasses for focusing heat on small quantities of solid, allowed Joseph Black,Henry Cavendish, Joseph Priestley and Karl Scheele, amongst others, to make numerousdiscoveries.The air was no longer thought of as a single substance. Various ‘airs’ wereidentified. ‘Fixed air’ (carbon dioxide), ‘inflammable air’ (hydrogen), ‘dephlogisticated air’(oxygen) and ‘phlogisticated air’ (nitrogen) all made an appearance. The term ‘gas’ wasnot in general use at the time.

The phlogiston theory may have had general acceptance but Antoine Lavoisier had hissuspicions.When he heard from Priestley of the discovery of dephlogisticated air – airthat has lost all its phlogiston – he embarked on a series of experiments aided by hisyoung wife. Lavoisier’s experiments led him to introduce a new system of chemistry,which used new ideas and new names for many substances. Lavoisier identified aboutthirty substances as elements – substances that could not be broken down into anythingsimpler by any chemical means. Lavoisier’s list of elements was not completelyrecognisable by today’s understanding of the term. He included compounds such as lime(calcium oxide) and magnesia (magnesium oxide) which he suspected were notelements, and those imponderable fluids, light and caloric. He also considered‘oxymuriatic acid gas’ to be a compound of oxygen and an unisolated element. It wasHumphry Davy who proved this false and gave oxymuriatic acid its new name,‘chlorine’.

Some of the chemists of the time, such as Joseph Black, adopted Lavoisier’s theory whileothers like Priestley remained staunch phlogistonists.

Atomism revivedAlthough Newton was convinced that matter was particulate, the concept of the atom wasnot well developed until the early nineteenth century. John Dalton was originallyinterested in meteorology before embarking on a vast number of experiments measuringthe properties of gases and vapours, individually and in mixtures. He developed his atomictheory almost as an aside and it takes up just a small part of his book, A New System ofChemical Philosophy. He stated that matter consisted of indivisible atoms, that all the atomsof an element were the same and that atoms could join together in simple ratios.Dalton used his ideas to work out a list of comparative atomic weights. Dalton’s ideasprovided a new impetus to the study of elements, and set the scene for decades ofexperiments in which substances in chemical reactions were very carefully weighedbefore and after reacting.

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Not everyone agreed on the interpretation of Dalton’s atomic theory. Dalton and JönsJacob Berzelius did not agree on whether atoms only combined in the simplest possibleratios; Dalton insisted water was HO while Berzelius opted for H2O. Neither of themaccepted Amedeo Avogadro’s idea of molecules of elements such as oxygen (O2). Indeedsome chemists refused to accept that the atomic theory was anything more than a usefulmodel. Friedrich Ostwald insisted until the end of the nineteenth century that the lackof direct evidence for atoms showed that they were a figment of chemists’ imagination.

Discovering more elementsThe work of the alchemists had added only a few elements to those known to theGreeks and Arabs of classical times. Phosphorus was perhaps the most exciting discoveryof the seventeenth century.The eighteenth century added a number of gases, but thedevelopment of new techniques in the nineteenth century resulted in a huge increase inthe number of identified elements.

The voltaic pile, invented by Alessandro Volta in 1799, was an important tool. HumphryDavy was the first to use electrolysis to identify new elements, and swiftly isolatedsodium, potassium, magnesium and calcium. He also recognised aluminium as anelement. In the mid-nineteenth century Robert Bunsen and Gustav Kirchoff developedthe spectroscope which allowed chemists to identify elements by the colours of the lightthey emitted when heated.With this technique it was possible to detect even very rareelements in minerals.

Ordering the elementsBy the 1850s over fifty elements were known and the picture was becoming veryconfused. It wasn’t helped by confusion over atomic weights, which was not resolveduntil after the Karlsruhe conference of 1860.At the conference, Cannizzaro presented apamphlet that put forward the arguments for accepting Avogadro’s ideas on moleculesand a system of relative atomic weights.

Various chemists had recognised atomic weight as being a unique property of eachelement and looked for patterns relating it to the chemical properties of the elements.Johann Döbereiner developed triads.These were groups of three elements that hadsimilar properties, and the average of the atomic masses of the lightest and heaviestequalled the atomic mass of the middle one (e.g. 7Li, 23Na, 39K).A.E Beguyer deChantcourtois and John Newlands both arranged the elements in order of atomicweight. De Chantcourtois then arranged the elements in a spiral and found that somesimilar elements fell close together. Newlands noticed that some similar elements fell atintervals of eight like musical octaves. None of them convinced their peers that therewas an underlying order to the elements.

Mendeleev had better luck largely due to the realisation that there were yet moreelements to discover. Using the newly accepted atomic weights, formulae of the oxidesand the properties of each known element, he was able to present his Periodic Law andpredict the properties of some, as yet, undiscovered elements.When these elements(germanium, gallium and scandium) were discovered, Mendeleev’s law was ‘proved’.

In the late 1890s the Periodic Law was tested by William Ramsay’s discovery of a wholenew set of elements, the Noble Gases.The fact that their atomic weights allowed themto fit snugly into the Table as a separate group (except for a small problem of argonbeing slightly heavier than potassium) gave added weight to Mendeleev’s law.



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Breaking atomsWhile the start of the nineteenth century saw the birth of the atomic theory, the end ofthe century saw Dalton’s indivisible atoms begin to crumble.Thomson’s measurement ofthe mass and charge of ‘corpuscles’ (which were soon to be re-named as electrons)showed that the atom had to have a structure.Thomson’s ‘plum pudding’ model of theatom in which thousands of electrons floated in a massless, positively charged puddingdid not last long.

The discovery of radioactivity by Henri Becquerel and Marie Curie gave chemists newtools for probing the atom. Ernest Rutherford was the supreme experimenter.Aided byFred Soddy, Hans Geiger, Ernest Marsden, Henry Moseley, and James Chadwick, heidentified the atomic nucleus and the proton.With Niels Bohr providing theoreticalconcepts, based on the new quantum theory, the atom gained a whole new structure.Chadwick’s discovery of the neutron in 1932 completed the trio of particles that makeup atoms. Further discoveries about the nature of matter lie in the province of theparticle physicists.

Radioactivity and artificial elementsThe discovery of radioactivity also provided another tool to identify new elements –radium and polonium by Marie Curie, and protactinium by Otto Hahn and LiseMeitner, amongst others. Radioactivity also allowed chemists to achieve the goal of thealchemists – the transmutation of elements. Bombarding targets of one element withparticles emitted by radioactive materials or by particles accelerated in a cyclotron, filledin the gaps in the Periodic Table – technetium being the last – and then allowed thePeriodic Table to be extended almost indefinitely. Glenn Seaborg was involved in thediscovery of most of the transuranic elements from neptunium up to number 106(seaborgium) and beyond. His chemical methods for separating plutonium wereimportant in the development of the atomic bomb.



E The characters

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This section provides a brief biography of each character included in Elements and Atoms.They are presented here in the same order as they are presented in the text on the CD.In some cases this section provides additional information on events that occurred afterthe date that each character ‘narrated’ their life story in the CD text.

Democritus (470 – 400 BCE)Greek philosopher. Democritus developedhis tutor, Leucippus’ idea that everything inthe world was made of tiny indivisibleparticles, which he called ‘atoms’. He usedthis idea to explain the phenomena of smelland taste.

Aristotle (384 – 322 BCE)Greek philosopher.Aristotle adopted anddeveloped earlier ideas of the four elementsusing his powers of observation, reason andargument. He knew of gold, silver, mercury,iron, copper, tin, lead, carbon, and sulfur, andconsidered them all as different mixtures ofthe four elements.

Jabir ibn Hayyam (721 – 815 CE)(known as Geber in Europe)Persian alchemist. Jabir was one of the greatArabian practical philosophers whodeveloped the idea of ‘Principles’ throughexperiment and observation.

Muhammad ibn Zakariyya al-Razi(854 – 930 CE) (also known as Rhazes)Persian doctor. Rhazes did not agree withalchemical ideas. He developed manyexperimental techniques and he dividedsubstances into animal, vegetable and mineral,and further subdivided the class of minerals.

Roger Bacon (1214 – 1292)English monk. Bacon was a link between theArabian alchemists and the EuropeanRenaissance philosophers. He analysed andcommented on the Greek and Arabic worksthat had newly arrived in Northern Europe.Bacon recognised the need for experimentsalthough he did not carry out manypersonally. His scientific thinking led totrouble with the church authorities.

Paracelsus (Theophrastus Bombastusvon Hohenheim) (1493 – 1541)German physician and chemist. Paracelsuswas the first to use new inorganic substancesas medicines. He developed the ‘mercury,sulfur, salt’ idea, and upset a lot of peoplewith his arrogance.

Robert Boyle (1627 – 1691)Irish-English natural philosopher. Boyle was awealthy experimenter who began as analchemist but became disillusioned with thefailure of alchemical ideas. Boyle suggestedthat elements were substances that could notbe decomposed. He experimented with (butdidn’t discover) the new element, phosphorus.

Georg Stahl (1660 – 1734)German chemist/physician. Stahl developedthe phlogiston theory which suggested thatwhat we now consider as elements weremixtures of an elemental calx and phlogiston.Phlogiston is the principle of fire.

Joseph Priestley (1733 – 1804)English preacher and chemist. Priestley wassupported by a number of wealthygentlemen. He was a staunch supporter ofthe phlogiston theory but he also discoveredmany gases, particularly dephlogisticated air(oxygen). i.e. - air that has lost phlogistonand hence has a great affinity for it.

Henry Cavendish (1731 – 1810)English chemist. Cavendish was a wealthyrecluse devoted to experimental science.He carried out a lot of work on gases in theair and showed that water consisted offlammable air (hydrogen) and dephlogisticatedair (oxygen).The Cavendish Laboratory(belonging to the University of Cambridge)was endowed from some of the money he leftwhen he died.

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Antoine Lavoisier (1743 – 1794)French chemist and tax collector. Lavoisierwas assisted in his experimental work by hisyoung wife, Marie. He used controlledexperiments to overturn the acceptedtheories of chemistry and replaced themwith a new system. His chief contributionswere the oxygen theory of combustion andthe definition of an element. His oxygentheory of combustion suggested that whensubstances burn they combine with oxygento form new substances. He listed aboutthirty elements but included some nowknown to be compounds (lime, salt), andsome ‘imponderable fluids’ e.g. caloric (heat).Lavoisier was tried for being a tax collectorduring the French Revolution, found guiltyand guillotined.

John Dalton (1766 – 1844)English scientist. Dalton came from arelatively poor background and was a teacherbefore devoting himself to research.His interest in gases developed from studiesof meteorology, and his ideas about atomsgrew out of his experimental workmeasuring the properties of various gases.His atomic theory suggested that atoms werehard, indivisible spheres. Dalton devised asystem of symbols to represent atoms ofelements. He measured the atomic masses ofsome elements (inaccurately by modernstandards). He suggested that atoms couldonly combine with atoms of other elementsand in the simplest ratios i.e. water was HO.

Humphry Davy (1778 – 1829)English chemist. Davy came from a relativelypoor background, but made his markon English society as Director of the RoyalInstitution. He used the new science ofelectrolysis to isolate sodium, potassium,magnesium and calcium. He alsodemonstrated the existence of aluminium.He proved that chlorine was an element.

Jöns Jacob Berzelius (1779 – 1848)Swedish chemist. Berzelius supported Daltonbut devised a system of letters to representelements, instead of using Dalton’s symbols.He produced more accurate lists of atomicmasses. He thought that water was H2O (or rather HOH), but did not acceptAvogadro’s suggestion of diatomic molecules.

Robert Bunsen (1811 – 1899)German chemist. Bunsen inventedspectroscopy with his colleague, Kirchoff, andused it to discover rubidium and caesium.

Stanislao Cannizzaro (1826 – 1910)Italian chemist and an ardent nationalist.Cannizzaro supported Avogadro’s hypothesisabout diatomic molecules and, by force ofargument in a privately published pamphlet,convinced the chemists who attended theKarlsruhe Conference in 1860.

Dmitri Mendeleev (1834 – 1907)Russian chemist. Mendeleev drew on hisknowledge and experience of working withelements to write a much respected textbook.After much thought, and trial and errorhe published his Periodic Law in 1869 andpredicted the existence of three elements,which were found in the years that followed.He insisted that some atomic weights (eg. tellurium or iodine) had been measuredincorrectly because they fell in the incorrectorder according to their chemical natures.

William Ramsay (1852 – 1916)Scottish chemist. Ramsay followed up anobservation of Lord Rayleigh and of HenryCavendish a century earlier, and discoveredargon. He then discovered helium in rocks(previously only observed in the Sun’sspectrum) and was then able to separateneon, krypton and xenon from the air byfractional distillation. He was knighted in1902 and awarded the Nobel Prize forChemistry in 1904.



CHARACTERS

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Joseph John Thomson (1856 – 1940)English physicist.Thomson was initially atheoretical scientist, but his ingeniousexperimental ideas led to him being madeDirector of the Cavendish laboratory inCambridge.Thomson was awarded the 1906Nobel Prize for Physics (for work on gases),and knighted in 1908.

Ernest Rutherford (1871 – 1937)New Zealand scientist. Rutherford workedunder Thomson before running his ownlaboratories in Montreal and Manchester.He later succeeded Thomson at Cambridge.He collected the evidence required to buildthe modern (that is, GCSE style!) model ofthe atom.

Frederick Soddy (1877 – 1956)British chemist. Soddy worked withRutherford in Canada before leading hisown departments in Scotland and England.His work on radioactivity lead to theconcept of isotopes.

Niels Bohr (1885 – 1962)Danish physicist. Bohr worked withRutherford in Manchester before running hisown department in Copenhagen.He combined Planck’s quantum theory withRutherford’s experimental evidence todevelop the electron shell theory. Bohr wasawarded the Nobel Prize for Physics in 1922.

Marie Curie (1867 – 1934)Polish scientist. Marie Sklodowska settled in France and married Pierre Curie, an older and established physicist.The Curieswere interested in Bequerel’s discovery of radioactivity.They investigated the phenomenon ofradioactivity and discovered radium andpolonium. Marie Curie set up the RadiumInstitute, which made further discoveries ofradioactive elements and pioneered themedical uses of radium and other radioactivematerials. Her notebooks from the 1890s arestill too radioactive to handle.

James Chadwick (1891 – 1974)English physicist. Chadwick worked withRutherford at Manchester and Cambridge,with a spell in a German internment camp inbetween. He discovered the neutron, whichRutherford had suggested should make upthe mass of the nucleus along with theproton. Chadwick was knighted in 1945.

Glenn Seaborg (1912 – 1999)American chemist. Seaborg worked forLawrence on the first cyclotron and tookpart in the discovery of neptunium andplutonium. He took charge of the projectand had a part in discovering most of thetransuranic elements discovered since.He was an advocate of the peaceful uses ofnuclear power.

Contemporary fictional characters

Sandra BanningA radiochemist who works for amultinational company, producing radioactivematerials for the medical industry.

Dr Arvinda PatelA medical doctor who makes use ofradioactive materials in diagnosis andtreatment.

Melanie ProctorA representative of an organisation that warnsabout the dangers of the use of radioactivity.

Bill ParsonsA patient who has undergone proceduresusing radioactive materials.

A TV presenter and three teenage charactersare also provided, but have no associated text.



F Matching charts

Key Stage 4 Sc1 Scientific enquiry


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About the interplay between empirical questions,evidence and scientific explanations using historical andcontemporary examples (for example, Lavoisier’s workon burning, the possible causes of global warming).

That it is important to test explanations by using themto make predictions and by seeing if evidence matchesthe predictions.

About the ways in which scientists work today and howthey worked in the past, including the roles ofexperimentation, evidence and creative thought in thedevelopment of scientific ideas.

Activity

1.1, 1.2, 2.1, 2.2,3.1, 3.2, 4.1, 4.2, 7.1,7.2, 7.3

2.1, 2.2, 4.1, 4.2, 5.1,5.2

1.1, 1.2, 3.1, 3.2, 4.1,4.2, 5.1, 5.2, 6.1, 6.2

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2.1, 2.2, 3.1, 3.2, 4.1,4.2, 5.1, 5.2

1.1, 1.2, 2.1, 2.2,3.1, 3.2

1.1, 1.2, 4.1, 4.2,5.1, 5.2, 6.1, 6.2, 7.1,7.2, 7.3

7.1, 7.2, 7.3

Statement

How scientific ideas are presented, evaluated anddisseminated (for example, by publication, review byother scientists).

How scientific controversies can arise from differentways of interpreting empirical evidence (for example,Darwin’s theory of evolution).

Ways in which scientific work may be affected by thecontexts in which it takes place (for example, social,historical, moral and spiritual), and how these contextsmay affect whether or not ideas are accepted.

To consider the power and limitations of science inaddressing industrial, social and environmental questions,including the kinds of questions science can and cannotanswer, uncertainties in scientific knowledge, and theethical issues involved.

Matching chart for English National Curriculum and Elements and

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Matching chart for Welsh National Curriculum and Elements and Atoms

1

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Statement

The Nature of Science

To consider different sources of information, includingthat obtained from their own work and informationfrom secondary sources.

How creative thought as well as information may berequired in arriving at scientific explanations.

About the work of scientists and the role ofexperimental data, creative thought and values in theirwork and in developing scientific ideas.

Communication in Science

To search systematically for, process and analyseinformation for a specific purpose, using ICT to do soon some occasions.

Activity

1.1, 1.2, 2.1, 2.2, 3.1,3.2, 4.1, 4.2, 5.1, 5.2,6.1, 6.2, 7.1, 7.2, 7.3

4.1, 4.2

1.1, 1.2, 2.1, 2.2, 3.1,3.2, 4.1, 4.2, 5.1, 5.2,6.1, 6.2

1.1, 1.2, 2.1, 2.2, 3.1,3.2, 4.1, 4.2, 5.1, 5.2,6.1, 6.2, 7.1, 7.2, 7.3


1

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4

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Statement

The Nature of Science

To use and consider a variety of sources of information,both that obtained from their own work and secondarysources, including ICT.

To recognise that scientific controversies arise fromdifferent interpretations and emphases placed on information.

To consider the ways in which scientific ideas areaffected by social, political and historical contexts inwhich they develop, and how these contexts may affect whether or not the ideas are accepted.

Activity

1.1, 1.2, 2.1, 2.2, 3.1,3.2, 4.1, 4.2, 5.1, 5.2,6.1, 6.2, 7.1, 7.2, 7.3

2.1, 2.2, 3.1, 3.2, 4.1,4.2, 5.1, 5.2

1.1, 1.2, 4.1, 4.2,5.1, 5.2, 6.1, 6.2, 7.1,7.2, 7.3



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Elements and Atoms also covers the following statements.

Key Stage 3

Key Stage 4

Statement covered

1b, 1c, 1d, 1e, 1g, 1h, 2g, 3a

1a, 1b, 1c, 1d, 1f, 2g, 2h, 2k, 3a, 3b, 3d, 3f, 3g, 3h, 3i, 3k, 3l, 3m

Key Stage 3

Key Stage 4

Statement covered

1.1, 1.2, 1.4, 1.5, 1.6, 1.7, 1.9, 2.8

1.1, 1.2, 1.3, 1.4, 1.6, 2.11, 2.12, 2.15, 3.1, 3.3, 3.5, 3.6

Key Stage 4 6a, 6e, 6f

Properties and uses

Kinetic Theory

Key Stage 3

e

a, c, e

Key Stage 4

a, b, c, d, e

Sc4 Physical processes

ENGLANDSc3 Materials and their properties

Key Stage 4 6.1, 6.6, 6.7

Sc4 Physical processes

WALESSc3 Materials and their properties

Materials from Earth

Level E

Level F

Changing materials

Level D

Level E

Statement covered

Describe the particulate nature of solids, liquids and gasesand use this to explain their known properties.

Describe what is meant by an element.

Describe some features of the structure of the atom.

Describe some characteristic features of the periodic table.

Describe what happens when materials are burned.

Describe how metal elements can be extracted fromcompounds in the Earth’s crust.

SCOTLAND5-14 Environmental Studies: Science

NORTHERN IRELANDMaterials and Uses


1 What are elements?


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Learning objectivesStudents have the opportunity to learn:� that ideas about elements have not always been the same � that not all scientific ideas were based on experimental evidence� that present day scientists rely on experimental evidence to test theories� what our modern idea of an element is (pupils may need some guidance with this).

Learning outcomesStudents:� answer questions by extracting information from text provided (Activity 1.1,Activity 1.2)� produce a storyboard showing how ideas about elements have changed, and some of the

evidence for different ideas (Activity 1.1,Activity 1.2)� produce arguments emphasising the importance of experimental evidence (Activity 1.2C).

Activity levels KS3 NC Statements

Background informationThese activities explore the changes in ideas about the nature of elements.The opinion of the Greek philosophers, based on observation and reason, was that everything is made up offour elements: Earth,Air, Fire and Water.The concept was developed by Arabic and Medievalalchemists into the theory of Principles - each substance is a mixture of mercury, sulfur andsalt.This was the basis of the idea that gold could be obtained by carrying out variousreactions on cheaper metals.The idea was that by changing the proportion of the variousPrinciples in a substance, one metal could be turned into another.Controlled experiments that commenced in the seventeenth century provided evidence thatled to the new system of chemistry put forward by Lavoisier, on which our modern idea ofelements is based.

Prior knowledgeNone, although some teachers may prefer to carry out this activity after students have beentaught the modern definition of an element.

Activity 1.1 Changing ideas about elementsStudents are provided with a set of frames showing scientists who helped to develop ideasabout elements, and are given questions to be answered using the information provided via thetext window.They can then go on to make the storyboard into a proper presentation byadding audio, props etc.The activity could be extended by asking pupils to add frames forscientists such as Georg Stahl and Henry Cavendish.

Sc1 Sc3

KS3 1a, 1c 1d, 1e, 1g, 1h

KS4 1b, 1c 3a

Activity KS3 KS4

1.1 Most All

1.2 Some Most


TEACHER’S N

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Activity 1.2 Arguing about elementsThis is similar to Activity 1.1 in that students are asked to find out about different ideas andthe evidence for them, but fewer prompts are provided. Once students have looked up therelevant information, they are asked to create their own storyboard to show an imaginarymeeting between Aristotle and Boyle.This is a good opportunity to bring out the importanceof experimental evidence in formulating and testing scientific theories.

Characters: Aristotle, Jabir ibn Hayyan, Paracelsus, Boyle, Priestley, Lavoisier.Students doing Activity 1.1C may also need Stahl and Cavendish.

Backgrounds: Greek Lyceum, medieval laboratory, Boyle’s laboratory, Laboratory in 1700s, Lavoisier’s laboratory, modern laboratory.

Props: Symbols for elements. Other general props such as bottles, books etc.may also be useful.

Lesson ideas� Start with a brainstorming session to find out what students think an element is (assuming

this has not already been covered in science lessons).� Explain to students that ideas have not always been the same, and that they are going to

look at how ideas have changed.� Hold a plenary session at the end of the lesson to discuss why people changed their ideas,

and to confirm that all students understand our modern definition of an element.

1 A substance that could not bedecomposed by any means.

2 Oxygen – because we now know thatacids do not have to contain oxygen.

3 a) alumina, magnesia, silica.b) They are all oxides and so must

contain oxygen as well as a metal.c) He could not break them down so he

assumed that they were elements.

4 Sulphuric acid, H2SO4; water, H2O;hydrochloric acid, HCl; copper sulphate,CuSO4; sodium hydroxide, NaOH.

5 The symbols should reflect the propertiesof the elements.

6 Using symbols makes it easier forscientists to communicate – it does notmatter what language they speakbecause the symbols will stay the same.

7 The web site www.chemicalelements.comhas an interactive periodic table thatpupils can use to extract the followinginformation:

Iron: Fe - from the Latin word ferrum (iron)

Silver: Ag - from the Latin word argentum (silver)

Gold: Au - from the Latin word aurum (gold)

Mercury: Hg - from the Latin word hydrargyrum(liquid silver)

Copper: Cu - from the Latin word cyprium, after the island of Cyprus where copper was abundant.

Answers to homework questions


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Everything around us is made up of combinations of around 115 elements.There have beenlots of different ideas about elements during the last 3000 years. Scientists have only agreed onour modern ideas in the last 200 years or so.

1.1 Changing ideas about elementsMake a storyboard that can be shown to younger children to explain how ideas aboutelements have changed.

A Open storyboard ‘Activity 1.1’.The frames show different scientists who had ideas aboutelements.At the bottom of each frame there are some questions.Use the text/audio symbol (the blue book) to open the text window and find the answersto the questions.You can use the search box at the top right of the text to look for keywords.Type your answers into the caption window in your own words or copy and paste from the text.

B Make the frames look more interesting by adding props. For instance, you could addsymbols representing Earth,Air, Fire and Water to Aristotle’s frame, or add the apparatusthat each scientist might have used in their experiments.

C Expand the storyboard to make the characters explain their own ideas.You can use theinformation you found when answering the questions. Remember to include our currentideas about atoms.

� You might need to add extra frames for each scientist so that they can explain their ideas fully.

� You can put their ideas into speech or thought bubbles, or you could use the sound filesprovided or record your own words.

� If you have time, you could add frames for scientists like Georg Stahl or Henry Cavendish,and explain their ideas about elements.

1.2 Arguing about elementsA Open storyboard ‘Activity 1.2’.The frames show different scientists who had ideas about

elements.Add text for each scientist to show their ideas about elements, and the evidencethey had for their ideas.You can use the search box at the top right of the text window tolook for key words.You could add the text to the caption window at the bottom or addtext directly into the frame as thought and speech bubbles.

B Add suitable backgrounds and props in each frame to show where each scientist mighthave worked, and the kind of apparatus they may have used.

C What would Aristotle and Robert Boyle say to each other if they could have met? Create a new storyboard to show Aristotle explaining his ideas to Boyle, and then have Boyle try to explain to Aristotle why ideas based on experimental evidence are better.

� You could put each person’s speeches in speech bubbles.� You could use the recordings provided to make a

sound track.� You could write their speeches and record them if you

have a microphone.



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HOM

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These labels show the old names for some chemical compounds.

The names we use today for chemicalcompounds are based on the names of theelements in the compounds.

Antoine Lavoisier suggested many of thenames of elements that we use today.

He made a list of thirty three elements,which included hydrogen, oxygen andcarbon, as well as substances he calledmagnesia, alumina and silica. He did notjust invent names, but gave some elementsnames that meant something. For instance,hydrogen means ‘water producer’ andoxygen means ‘acid producer’.

1 What did Lavoisier think an element was?

2 Hydrochloric acid contains hydrogen and chlorine, but no oxygen.Now we know this information, which of Lavoisier’s names does not make sense?

3 Our modern names for three of Lavoiser’s ‘elements’ are aluminium oxide,magnesium oxide and silicon dioxide.a) What were Lavoisier’s names for these ‘elements’?b) How do you know from their modern names that they are not elements?c) Why didn’t Lavoisier know that these substances were not elements?

Questions 4-7 can be found over the page.

An element is asubstance that wehave not yet beenable to decompose

by any means.



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1 Alchemists used symbols for substances that were based on the magical properties thatthe substances were supposed to have.These are some of the alchemical symbols:

In the 19th century a scientist called John Dalton invented symbols for differentelements.These are some of his symbols:

The symbols we use for elements today were first used by Jöns Jacob Berzelius.Some of these symbols are obvious: for instance H represents hydrogen, and Orepresents oxygen.These modern symbols are used by chemists all over the world,no matter what language they speak.

4 Write out the names of these common laboratory chemicals and then add the correctformula from the list below:

sulphuric acid water hydrochloric acid sodium hydroxide copper sulphate

HCl CuSO4 NaOH H2O H2SO4

5 Pick four elements and design your own symbols for them, based on what you knowabout their properties. For instance, hydrogen burns easily, so you might want to design a symbol for hydrogen that includes flames.

6 Why do you think it is important that all chemists use the same symbols for elements?

7 Some of our modern symbols for elements do not match the name of the element.Find out the symbols for these elements, and find out why they have these symbols.a) iron d) mercuryb) silver e) sodiumc) gold f) copper

You will find some useful web addresses at www.peopleinscience.co.uk

sulfur silver mercury phosphorous copper

sulfur silver mercury gold copper

1 What are elements (cont.)


2 Ideas about burning


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Learning objectivesStudents have the opportunity to learn:� that ideas about burning have not always been the same � that theories change when new evidence is found� that present day scientists rely on experimental evidence to test theories� about our current ideas on burning.

Learning outcomesStudents:� answer questions by extracting information from text provided (Activity 2.1,Activity 2.2)� produce a storyboard showing how ideas about burning have changed, and some of the

evidence for different ideas (Activity 2.1,Activity 2.2)� produce arguments for and against the theory of phlogiston, based on information

provided, and put these arguments into their own words (Activity 2.1,Activity 2.2).

Activity levels NC Statements

Background informationEarly ideas about burning saw fire as belonging to the combustible material – for instance the element, Fire, was contained in wood.This idea became a sophisticated theory in the hands of Georg Stahl. The phlogiston theory stated that there was an element calledphlogiston that was released when substances were burnt. It had negative mass (to account forthe rise in mass of substances when they burnt) and only a certain amount would be releasedif something was burnt in a closed environment (which accounted for the fact that thingsstopped burning after a while in a closed container). The theory made predictions that couldbe tested and shown to be true.There were always opponents, however, who saw the increasein mass when some substances burned as an argument against the theory. It took the preciseand detailed work of Lavoisier to provide an alternative that answered the objections.Some chemists such as Priestley were not convinced.

Prior knowledgeStudents should be aware that chemical reactions happen when substances combine or splitapart. It is not essential that students have specifically covered combustion, although someteachers may prefer to carry out these activities after students have learnt about combustion.

Activity 2.1 What happens when things burn?Students are asked to complete a museum exhibit that explains how ideas about burning havechanged, and the role of experimental evidence in developing new ideas. Students are givenframes introducing Stahl, Priestley, Cavendish and Lavoisier, and asked questions to help themextract the relevant information from the text provided. Students are then asked to summarisethe two ideas in their own words, and to explain why we think our current ideas are correct.The activity is extended by asking pupils to edit storyboards and to add extra information intheir own words.

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Activity 2.2 A burning debate.The scene here is a TV studio, where Priestley and Lavoisier are being interviewed for adocumentary. They are asked about their ideas and the evidence for them.The interviewerasks the questions, and students have to answer for the two scientists.The activity is extended by moving the scene to a Royal Society debate, and asking studentsto summarise the arguments for both sides in their own words, and then explain which theorythey would have supported, and why.

Characters: Stahl, Priestley, Cavendish and M and Mme Lavoisier,plus modern presenters.

Backgrounds: Laboratory in 1800s, Lavoisier’s laboratory, Royal Society Hall,TV studio.

Props: General props such as bottles, books, etc. may be useful.

Lesson ideas� Start with a brainstorming session to find out what students think happens when things

burn (assuming this has not already been covered in science lessons).� Explain that ideas have not always been the same, and that students are going to look at

how ideas have changed.� If necessary, groups of students can be given different scientists to research and their

individual storyboards can be combined later.� Hold a plenary session at the end to discuss why people changed their ideas, emphasising

the role of new evidence in the development and acceptance of new ideas, and to confirmthat all students understand our modern theory of what happens when things burn.You could also discuss how ideas were communicated.

1 Phlogiston was a substance thatscientists thought was given out whensomething burnt.

2 Phlogiston means flammable.

3 The phlogiston was released into the air.

4 If a metal gained phlogiston then wewould expect it to get heavier not lighter. (Note: this problem was recognised atthe time but it was suggested thatphlogiston could have negative weight.)

5 a) A metal burnt in air gave off phlogiston.

b) There should have been more air.c) Lavoisier found that there was less air.

6 a) You would expect the mass to be greater (assume that pupils do not know about the idea of negative mass).

b) The mass would have been less.c) Lavoiser pointed out that the mass of

the mercury calx (or oxide) should have been greater but it was less – meaning something had been lost frommercury calx not gained.

7 Diagram should include flat wick,cylinder of fuel, chimney and some wayfor air to get to the wick.

8 The lamp provided the wick with a lot of air which meant that it could burnefficiently.

9 Karl Wilhelm Scheele (1742 – 1786).Scheele published a book in 1777 calledChemical Observations and Experimentson Air and Fire. He stated that therewere two gases in air and called them‘fire air’ and ‘vitiated air’. ‘Fire air’ wasoxygen and allowed substances to burn,‘vitiated air’ is nitrogen. He isolatedoxygen in 1772 - two years beforePriestly - but because he did not publishhis work quickly he was not recognisedas the discoverer of oxygen.

The following web address will be usefulfor answering this question:http://mattson.creighton.edu/History_Gas_Chemistry/Scheele.html



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You have all seen things burning – gas from a Bunsen burner, candles, or even logs in a fire.What happens to these substances when they burn? There have been lots of different ideasabout burning, and we are going to look at two of these ideas.

2.1 What happens when things burn?The Science Museum often has exhibitions explaining science.Sometimes these exhibits have films of actors pretending to bescientists explaining their ideas.You are going to make an exhibitthat explains different ideas about burning, and why peoplebelieved those ideas.

Your exhibit should be for people of your own age who have notstudied this subject.

A Open storyboard ‘Activity 2.1’.The frames show different scientistswho had ideas about burning.At the bottom of each frame there aresome questions.Use the text/audio symbol (the blue book) to open the text windowand find the answers to the questions.You can use the search box atthe top right of the text to look for key words.Type your answersinto the caption window in your own words or copy and paste fromthe text.

B Expand the storyboard to make each of the characters explain theirown ideas.You can use the information you found when answeringthe questions.

� You might need to add extra frames for each scientist.� You can put their ideas into speech or thought bubbles, or you could

use the sound files provided or record your own words.

� You can also add props to each frame to make them look moreinteresting.

2.2 A burning debateBefore new scientific ideas are accepted, scientists discuss them and examine the evidence that supports them.

A Open storyboard ‘Activity 2.2’.The frames show parts of an interview with JosephPriestley and Antoine Lavoisier.Use the text to find out what each scientist thought.You can open the text window byclicking on the text/audio symbol (the blue book). You can use the search box at the topright of the text to look for key words.Add speech bubbles or audio to the frames wherePriestley and Lavoisier are speaking, to make them answer the interviewer’s questions.

B Scientific ideas are often debated at conferences. Finish off the storyboard provided bysummarising the ideas on both sides in your own words, and then explaining which ideayou would support, and why.

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Before Lavoisier, scientists believed in the idea of phlogiston. Phlogiston was a substance,and the word phlogiston comes from the Greek word ‘phlogistos’, meaning flammable.Phlogiston could not be put in bottles or weighed.These are some of the things thatscientists said about phlogiston when Lavoisier was investigating burning in the eighteenth century.

1 What was phlogiston?

2 Why was it a good name to give something which was involved in burning?

3 What happened to the phlogiston when things were burnt?

4 Why do the last two parts of the information in the picture contradict each other?

Lavoisier used this huge apparatus to overthrow the idea of phlogiston.It focuses the Sun’s rays onto a substance so that it is heated to a very hightemperature. He used it to burn mercury in air. He measured the exactquantity of air that was left after the mercury had burnt. He showed that some of the air had been used up.Then he took the mercury(II) oxide whichhad been made. He heated this and foundthat the mercury oxide became puremercury again. He collected the mercuryand oxygen that had been formed.He measured the amount of oxygenproduced, and found that it was exactly the same amount which was taken up by the mercury when it wasoriginally burnt.

• When things are set on fire and burnt thephlogiston is released into the air.

• Wood loses weight when it burns.• Charcoal, which is left after wood is heated,

is almost pure phlogiston.• When a metal ore is heated with charcoal it

turns into a pure metal.• Charcoal gives phlogiston to the metal ore.• The weight of a metal produced by heating

with charcoal is less than the weight of theore it was made from.



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5 a) What did the phlogistonists say happened when a metal was burnt in air?b) If this was true, should there have been more or less air in the container after the

mercury was burnt?c) How did Lavoisier’s results contradict this idea?

6 Phlogistonists thought that if you added phlogiston to a metal calx (like the mercury oxide that Lavoisier had made), you would get the pure metal back again.a) Would the mass of the metal be more or less than the mass of the calx if phlogiston

had been added to it?b) Do you think that the mass of Lavoisier’s mercury at the end of the experiment was

more or less than the mercury oxide he had started with?c) How did Lavoisier’s result contradict the ideas of the phlogistonists?

One development from Lavoisier’s work on burning was a lamp. It was known as theArgand burner, and it was made in 1783. It had a flat ribbon wick, which dipped into a fuel contained in a cylinder.Air could reach the wick from both the inside and theoutside.There was a chimney on the lamp that produced an updraft of air.The lampgave a brilliant light, which was a brighter light than any light before it.

7 Draw a diagram to show the important features of this lamp.

8 Suggest why its light was brighter than any light before it.

9 Three people were involved in the oxygen story: Karl Scheele, Joseph Priestley, and Antoine Lavoisier. Find out about Scheele.Try to discover when and where he lived,and how he was involved in the discovery of oxygen.You will find some useful web addresses at www.peopleinscience.co.uk

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3 Ideas about atoms


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Learning objectivesStudents have the opportunity to learn:� that ideas about atoms were suggested by the ancient Greeks, but these ideas were not

based on experimentation� that new ideas are often only accepted when there is experimental evidence to back

them up� that the idea of atoms can explain the properties of solids, liquids and gases.

Learning outcomesStudents:� extract information from the text provided to explain different ideas about atoms (Activity

3.1,Activity 3.2)� summarise the changing ideas about atoms (Activity 3.1,Activity 3.2)� produce a story that demonstrates their understanding of how and why ideas changed, and

why Dalton’s ideas were eventually accepted (Activity 3.2)� use ideas about atoms to explain the properties of solids, liquids and gases (Activity 3.1C).

Prior knowledge Some teachers may prefer to carry out these activities after students have been taught themodern definition of atoms. Students carrying out Activity 3.1C should have studied particletheory and have a basic understanding of how particles are arranged in solids, liquids and gases,and how this explains the physical properties of substances.


Background informationThe idea that matter is made up of particles goes back to at least the time of Democritus inAncient Greece. It was opposed because philosophers such as Aristotle could not accept theempty space that must exist between particles.The particle theory reappears in various guises –Newton and Boyle refer to ‘corpuscles’ rather than atoms or particles. Dalton presented hisatomic theory in 1805, as part of a much longer work on the properties of gases. His mostimportant contribution was to state that each element had its own type of atom and that theycombined in simple ratios to form ‘compound atoms’. Dalton’s idea of atoms as hard sphereswas not accepted universally and even at the end of the 19th century some chemists continuedto deny the existence of atoms because of the lack of direct evidence.

Activity 3.1 Yesterday’s World – Ideas about atomsStudents produce a TV programme introducing Dalton’s ideas about atoms, and howDemocritus had similar ideas centuries before.As an extension, pupils can create their ownstoryboard showing how ideas about atoms can help to explain the properties of solids,liquids and gases.

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Activity 3.2 The importance of evidenceStudents produce a photo story illustrating the importance of evidence in the acceptance ofscientific ideas. Students are provided with headlines, and have to produce their own text andpictures based on the information provided. Students are then asked to find information onrecent evidence for atoms. For example they could find out about scanning electronmicrographpictures of atoms. Suitable web links can be found on the People in Science website.

Students can then print out their storyboard in the form of a magazine story. Differentiationon this activity is likely to be mainly through outcome.

Characters: Democritus, Dalton, modern characters.

Backgrounds: Greek house or lyceum, Dalton’s study,TV studio.

Props: General props such as bottles, books, etc. may be useful.

Lesson ideas� Explain that ideas about matter being made of atoms were put forward over 2000 years

ago, but were not generally accepted until Dalton put the ideas forward again around 200 years ago.

� If time permits at the end of the lesson, arrange for students to view each others’storyboards, particularly if different groups have carried out different activities.

� Hold a plenary session asking students to reformulate their ideas about why it took so longfor ideas about atoms to be accepted, and why these ideas are so important for science today.

1 Atoms can not be broken down andatomos means ‘uncuttable’. (Note: asstudents move to KS4 they will be taughtabout subatomic particles.)

2 The diagrams should show a series ofpictures – one to show atoms, one toshow that an atom of one element is thesame as another atom of the sameelement but different to an atom of adifferent element, and one to showatoms combining.

3 a) True.b) False – atoms are small particles,

elements are substances that consist of only one type of atom.

c) False – atoms in an element are the same as each other but are different to atoms of different elements.

d) False – molecules of water are the same as each other.

e) False – a molecule of water will only contain atoms of oxygen and hydrogen.

4 The diagrams should reflect the text i.e.atoms of metals being spiked by the acidand then floating apart.

5 He could have agreed with them – theydo not contradict his theory. (Note: theanswer given could be justified eitherway but it should contain a reasonableexplanation.)

6 The poster should contain the correctideas about atoms but could combine itwith Dalton’s initial thoughts.

7 Answers should resemble the model thatstudents are taught at KS4 i.e. a nucleusof protons and neutrons surrounded byelectrons in shells. A suitable web site iswww.gcsechemistry.co.uk. Furtherweblinks can be found on the People inScience website.




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You have probably heard of atoms, but did you know that the first person to talk abouteverything being made of atoms lived over 2000 years ago? However, most scientists did notbelieve that atoms existed until John Dalton explained his ideas about 200 years ago.

3.1 Yesterday’s World – Ideas about atomsTV programmes like Tomorrow’s World often report on new scientific ideas or discoveries.If TV had existed 200 years ago, you might have been able to make a programme aboutJohn Dalton’s ideas about atoms.

A Open storyboard ‘Activity 3.1’.The frames show part of a TV documentary.Add speechbubbles to answer the interviewer’s questions.You will find the answers in the text window.To get to the text window, click on the text/audio symbol (blue book).You can use thesearch box at the top right of the text to look for key words.

B Add some new frames to the end of the storyboard so that Dalton can finish explaining hisideas about atoms.Then you can add a frame that uses the TV studio and the interviewercan summarise his ideas.

C Make a new storyboard which summarises Dalton’s ideas, and then use these ideas aboutatoms to explain the properties of solids, liquids and gases. Choose your own setting andpresenter. (Hint: if you want to draw particle diagrams, you could use the letter ‘o’ torepresent a particle.)

3.2 The importance of evidenceDalton’s experiments helped him to work out that substances were made of atoms.You can use Kar2ouche® to compose a ‘Photo Story’ for a magazine.

A Open storyboard ‘Activity 3.2’.The first frame is done for you, and the headings for theremaining frames are given.Write a short paragraph to go under each heading.You can copy and paste the words of the characters, or you can write in your own words.You can use the search box at the top right of the text window to look for key words.

B Add pictures to your storyboard to illustrate what you have written, then print it out.You need to choose the right print format so that all your writing is printed.

C Add a frame with the headline ‘We now know about atoms because…’. Find out aboutrecent evidence for atoms from a book or the internet and add some information to theend of the storyboard.You will find web addresses to help you on the websitewww.peopleinscience.co.uk


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The Greek word atomos means ‘uncuttable’.This is where the word atom comes from.John Dalton did a lot of experiments and thinking about atoms. He thought that:

1 Suggest one reason why the word atom is used.

2 Draw a series of labelled pictures or diagrams to illustrate Dalton’s ideas about atoms.You could show carbon atoms and oxygen atoms, then show molecules of carbon dioxide.

3 Decide which of these statements are true and which are false. Rewrite the false statementsso that they are correct:a) Everything is made of atoms.b) Elements and atoms are the same things.c) An atom of hydrogen is the same as an atom of oxygen.d) All molecules of water are different from each other.e) Sometimes water molecules contain oxygen and hydrogen, sometimes they contain

other atoms as well.

All matter is composed oftiny particles called atoms.

All atoms of the sameelement differ from atomsof other elements.

When a chemicalreaction takesplace atoms joinup to makeparticles of a newsubstance, calleda compound.

All atoms of the same element areexactly alike in size and weight.

All compound atoms(molecules) of a particularcompound are exactly alike.

O Coxygen

All matter is made up of atoms

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Nicholas Lemery lived between 1645 and 1715. He said that the properties ofsubstances could be explained by the shape of their particles.He imagined that acid particles had sharp points that tore open metals. He thought thatthe spikes stuck into the small metal particles so that the light acid particles made theheavy metal particles float.This made a clear solution.If an alkali was added it broke the acid particles away from the spikes.The spikesremained in the metal particles, which then precipitated (formed a solid).

4 Draw a series of labelled pictures or diagrams to show Lemery’s ideas.The first one has been done for you.

5 How do you think John Dalton would have responded to these suggestions?

6 Write a paragraph or design a small poster to explain to people your age what atoms are.

7 Find out what we think atoms look like now – you can use books or the Internet.You will find some useful web addresses at www.peopleinscience.co.uk

acid particles with spikes

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3 Ideas about atoms (cont.)


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Learning objectivesStudents have the opportunity to learn:� the different ways in which scientists communicate and share ideas� that the work of a scientist usually depends on the work of others before him/her� how Mendeleev’s Periodic Table was developed, and why it became generally accepted� about other attempts to arrange the elements, and why they were not accepted.

Learning outcomesStudents:� answer questions by extracting information from text provided (Activity 4.1,Activity 4.2)� research other attempts to find a pattern for the elements (Activity 4.1C)� produce a storyboard showing how Mendeleev produced his Periodic Table (Activity 4.1)� write newspaper/magazine reports about the Karlsruhe conference and Mendeleev’s

discovery, demonstrating their understanding of the importance of the work done by otherscientists in providing Mendeleev with the information he needed, and in validating hisideas when new elements were discovered (Activity 4.2).

Prior knowledgeStudents should know what elements are, and that elements have different properties.They should also know about atomic mass, and that this quantity was also referred to as‘atomic weight’. Some teachers may also prefer that students already have some understandingof the importance of the Periodic Table to modern chemistry.


Background informationBy the 1850s there was a tremendous muddle with various systems of atomic weight in use.The confusion was only resolved after Cannizzaro circulated his pamphlet following theKarlsruhe Conference in 1860, Cannizzaro suggested the adoption of Avogadro’s hypothesiswhich said that atoms of the same element could join together and a system of atomic weightswith hydrogen equal to one.This then became the accepted system.Once a consistent set of atomic masses was available, various people began to see patterns inthe properties of elements. Mendeleev may not have been aware of many of these trial runs.His Periodic Table was based on atomic weight, patterns in the formulae of oxides, andsimilarities between certain elements. It was a success because it predicted the existence ofsome undiscovered elements.These elements were later discovered, and found to haveproperties very close to the properties Mendeleev had predicted.

Activity 4.1 Mendeleev and the Periodic Table 1Students produce a sequence of frames showing Mendeleev explaining how he developed thePeriodic Table.The frames are provided, and students are asked questions to help them extractthe relevant information.As an extension, pupils can be asked to research other ideas that hadbeen put forward for arranging the elements, and to illustrate these within their storyboard.Suitable weblinks can be found on the People in Science website.

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Activity 4.2 Mendeleev and the Periodic Table 2Students are asked to produce a report of the Karlsruhe conference in 1860, and then toreport an interview with Mendeleev after he had published the second version of his PeriodicTable in 1871.Writing frames are provided in Word, at two levels.Activity 4.2a is moresupportive and includes more prompts to help students to extract the relevant information.

Characters: Cannizzaro and Mendeleev. Dalton, Berzelius and Modern charactersmay also be useful.

Backgrounds: Priestley’s laboratory, Dalton’s study or laboratory in the 1800s (any ofwhich could be used for the setting for Mendeleev), Royal Society Hall.

Props: General props such as bottles, books etc., may be useful.

Lesson ideas� Start by holding a brief brainstorming session to discuss how elements differ from one

another in terms of physical and chemical properties.� If students already know that the elements are arranged in order of atomic number, tell

them that protons were not discovered until after Mendeleev had invented the PeriodicTable. It may also be worth pointing out that not all the elements were known about atthe time, and the formulae for different compounds were not known.Therefore, theatomic masses of some elements were not known accurately.

� If students have not covered the Periodic Table in any detail, start with a brief explanation ofwhy it is useful in terms of predicting the properties of elements in the various groups.

� A plenary discussion should bring out the importance of scientists working together andsharing information such as at conferences and in scientific papers. Students could alsodiscuss how this sharing of information happened in Mendeleev’s day and the differentways in which it could happen today.

1 Two – one of hydrogen and one of oxygen

2 Three – one of oxygen and two of hydrogen

3 Diagram should show an empty circleplus two circles with dots in the centre.

4 Oxygen is 16 and carbon 24

5 Dalton said that water was one atom ofoxygen to one of hydrogen – theexperiment suggests that it is one ofoxygen to two of hydrogen.

6 He needed to put them in the correctorder so he had to be sure that theweights were accurate.

7 a) 72 or 73 c) Around 4.8 g/cm3

b) Around 800ºC

8 a) About -100ºC c) About 150ºCb) Around -65ºC d) Around 195ºC

9 Answers should explain that values liebetween the melting points and boilingpoints given.

10 Döbereiner arranged similar elementsinto groups of three such as Cl, Br, I.The atomic weight of the middleelement is approximately the average ofthe other two.Newlands put the elements into order ofatomic mass and realised that there wasa pattern in the properties that could beseen repeating every seven elements.De Chancourtois arranged the elementswith increasing atomic weight on acylinder.Meyer also arranged the elements inorder of increasing atomic weight butdid not publish his results until a yearafter Mendeleev.

Pupils could try www.britannica.com orwww.scienceworld.wolfram.com/biography as a starting point forresearch. The People in Science websitealso has useful weblinks.






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Many scientists looked for patterns in the elements, but it was not until Mendeleev puttogether his Periodic Table that most scientists accepted that there were patterns in theelements and their properties. Mendeleev could not have made his table without the work of other scientists who had worked out the atomic weights of different elements.Our modern name for atomic weight is atomic mass.

4.1 Mendeleev and the Periodic Table 1A Open storyboard ‘Activity 4.1’.The frames show Mendeleev thinking about elements.

At the bottom of each frame there are some questions.Answer the questions usinginformation from the text window. Click on the text/audio symbol (blue book) to look at and listen to the text.You can use the search box at the topright of the text to look for key words.You can answer in your ownwords, or copy and paste from the text provided.

B Make your storyboard more interesting by making Mendeleev explainhis ideas himself.

� You can add speech or thought bubbles to the frames, and add extraframes if you need them.

� You could add another character who is interviewing Mendeleev andasking him how he developed his ideas.

� If you have a microphone, you could record your own version ofMendeleev’s story.

C Find out about Newlands’ octaves, and Döbereiner’s triads.Add frames to your storyboard to illustrate these ideas.You will need to do someresearch to find the information you need.You will find some usefulweb addresses at www.peopleinscience.co.uk

4.2 Mendeleev and the Periodic Table 2Scientific conferences are often reported in newspapers or scientific magazines.You are going to produce a report of the Karlsruhe Conference, held in 1860.Your report will be written in ‘Word’, but you will need to use information from People in Science to help you to write the report.

A Open the Word document ‘Activity 4.2a’ or ‘Activity 4.2b’.Your teacher will tell you which one to use. Complete the report using information from the text window onCannizzaro and Mendeleev. Remember that you are writing a report for a newspaper or magazine. You can make your report more interesting by including quotes from the scientists.

B Write another report for a magazine, set in 1872.You have been sent to interviewMendeleev about his new Periodic Table, and you want him to explain how he developed his idea.

C Illustrate your reports by creating scenes within People in Science, and using the ‘copy’button to copy and paste them into your reports. Use different fonts or sizes of print tomake your reports look like magazine articles.




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When Mendeleev produced his Periodic Table, he needed to know the atomic weightsof different elements as accurately as possible. Chemists cannot weigh individual atoms,but one way of finding atomic weights depends on knowing how many atoms of oneelement react with a certain number of atoms of another element.

Hydrogen atoms and oxygen atoms can make water. John Dalton said that one atom ofhydrogen and one atom of oxygen make one molecule of water. He gave water theformula OH. He said this because he believed in the Principle of Simplicity, which statedthat if one atom of hydrogen was involved there had to be just one atom of oxygen.If we still believed this methane would have a formula of CH. Today we say the formulaof water is H2O and Methane is CH4. John Dalton said that the atomic weight ofhydrogen would be 1. Oxygen’s atomic weight was 7 and carbon’s atomic weight was 5.

Use this information and a copy of the Periodic Table to answer these questions.

1 How many atoms were there in John Dalton’s idea of a water molecule?

2 How many atoms are there in our modern idea of a water molecule?

3 John Dalton drew a water molecule like this:

Draw the modern version of a water molecule using John Dalton’s symbols.

4 What atomic weights do we use today for oxygen and carbon? (Today we call them atomic masses not atomic weights.)

In 1800 William Nicholson and Anthony Carlisle passed an electric current throughwater.They showed that when the water decomposed it produced twice the volume of hydrogen as oxygen.

5 How does this information challenge John Dalton’s theory?

In 1869 Mendeleev put together a Periodic Table. To do this he used atomic weights to arrange the elements.

6 Why was it important to Mendeleev that the atomic weights of the atoms of elementswere correct?

oxygen hydrogen

I need to knowaccurate atomic

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7 The diagram below shows part of Mendeleev’s Periodic Table, after Lecoq had discoveredthe element gallium.There is still an element missing.The missing element is germanium,which was discovered in 1880.

The diagram shows different properties of the elements around the missing element.Remember that atomic weight usually increases as you go across the table. Groups ofelements with similar properties go down the table.

Use the information in the table to make predictions about the missing element.Write down approximate numbers for these things:a) atomic weight b) melting point c) density

8 This table shows some properties of the elements in Group 7. Use the properties of theelements above and below to estimate the numbers for chlorine and iodine, and writethem down.

9 Explain how you worked out your answers to question 8.

10 Other scientists had tried to find patterns in the elements before Mendeleev.Use the internet to find out about one or more of these scientists:

Johann Döbereiner and his law of triadsAlexandre Béguyer de ChancourtoisJohn Newlands and his law of octavesLother Meyer

When you have found out about these people and their ideas draw up a timeline toillustrate how ideas changed with time.Log on to www.peopleinscience.co.uk for useful web links.

Element Melting point (ºC) Boiling point (ºC)

fluorine -220 -188chlorine (a) (b)bromine -7 59iodine (c) (d)astatine 302 337

AluminiumAtomic weight 27

SiliconAtomic weight 28Melting point 1410 ºCDensity 2.32 g/cm3

PhosphorousAtomic weight 31

GalliumAtomic weight 70 ?

ArsenicAtomic weight 75

IndiumAtomic weight 115

TinAtomic weight 119Melting point 232 ºCDensity 7.28 g/cm3

AntimonyAtomic weight 122

4 Atomic weights and the Periodic Table (cont.)


5 Inside the atom


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Learning objectivesStudents have the opportunity to learn:� about the structure of the atom� how ideas about atomic structure developed� that most recent and current research is carried out by teams of scientists� most research builds on the work of other scientists� that new ideas about atomic structure were based on experimental evidence.

Learning outcomesStudents:� answer questions by extracting information from the text provided (Activity 5.1,

Activity 5.2)� produce a storyboard outlining changing ideas about the atom, including some of the

evidence on which new ideas were based (Activity 5.1,Activity 5.2).

Prior knowledgeStudents should know that atoms are the smallest particle of an element, and that they consistof even smaller particles. Some teachers may also prefer that students know about protons,neutrons and electrons and energy levels.


Background informationDalton said that atoms were indivisible, but it became clear during the 19th century that theymust be able to carry positive and negative charges. During the 1890s the classical image ofmatter and energy began to break down.Thomson’s measurement of the mass and charge ofthe ‘corpuscles’ emitted in cathode rays lead to the idea that atoms have structure.The discovery of radioactivity provided chemists with the tools to probe the structure.Thomson’s ‘plum pudding’ model soon gave way to the Rutherford-Bohr nuclear atom, thanksto the innovative experimental work of Rutherford and his co-workers, Soddy, Geiger,Marsden, Moseley and Chadwick.

Activity 5.1 Inside the atom 1Students are provided with a sequence of frames showing the scientists who helped to developideas about atomic structure. Each frame includes questions to help students to extract therelevant information from the text.The first frame (Dalton) has been completed for them.As an extension, pupils can be asked to convert their answers into actual speech from thecharacters, and to add appropriate props to make a storyboard that can be viewed by others.The final frame of Activity 5.1 refers to the fact that we now know that protons and neutronscan also be broken down into smaller particles.Teachers may wish to ask pupils to investigatethese particles or they may wish to remove the last frame of the storyboard.

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Activity 5.2 Inside the atom 2This activity is similar to Activity 5.1, except that the storyboard only provides students withthe names of the scientists involved.

Characters: Dalton,Thomson, Rutherford, Soddy, Bohr, Chadwick, and TV presenter.

Backgrounds: Cyclotron, Dalton’s study, laboratory 1900 - 1960, modern laboratory.

Props: Atomic structure diagrams, and general props such as bottles, books, etc.may also be useful.

Lesson ideas� Find out what students already know about subatomic particles – even if students have not

yet studied the structure of the atom they may have heard of electrons from work on electricity.

� If students have not yet learned about protons and neutrons, you may wish to introducethe lesson by saying that we believe that atoms are made of even smaller particles, and thatthe lesson is looking at how these particles were discovered.

� At the end of the lesson, ask students to summarise the changing models of the atom.� You may also wish to point out that these particles are no longer the smallest particles

known, and that protons and neutrons are made up of even smaller particles.This ismentioned in the last frame of the activity provided, with the reassurance that students donot need to learn about these particles yet!

1 Diagram should show a beryllium atomwith the protons, neutrons and electrons correctly labelled.

2 The electron.

3 Neutrons are electrically neutral.

4 Atoms are split apart and this means thatwe can study what they are made up of.

5 Electrons are very tiny. Able studentsmay calculate that the size of an electronis approximately 4 x10 –11 mm.

6

7 a) A positive charge.b) They bounced off the dense and

positively charged nucleus.c) That the gold atoms had a centre and

that it was positively charged. d) That the electrons were around the

outside of the nucleus, not in the middle or throughout the atom.

8 We would expect pupils to explain thatthere are even smaller particles calledquarks and that they come in different‘flavours’. A suitable web site to look atis: www.pbs.org/wnet/hawking/strange/html/strange_quarks.html


Name of Where is it found Chargeparticle in the atom?

proton nucleus +1neutron nucleus 0electron outside nucleus in shell -1


5 Inside the atom


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Some scientists say that the greatest sentence in Science starts with,‘All things are made of atoms…’Scientists have thought about atoms and their structure for a long time.The timeline shows some of the people who have worked on the structure of atoms,and the models they suggested.

5.1 Inside the atom 1A Open storyboard ‘Activity 5.1’.The storyboard explains how the structure of the atom was

discovered.You have been given the names of the scientists who made some of the mostimportant discoveries. Look up each scientist in the text window, and then answer thequestions under each frame. Click on the text/audio symbol (blue book) to look at and listento the text.You can use the search box at the top right of the text to look for key words.

B Convert your answers to the questions into speech by adding speech bubbles or audio to each frame.Add props to the frames to make them look more interesting – for instanceyou could add pictures of the different models of the atom, or the apparatus used in the labs.

5.2 Inside the atom 2A Open storyboard ‘Activity 5.2’. Complete the storyboard to explain how the structure of

the atom was discovered.You have been given the names of the scientists involved, and somehints on what to write. Click on the text/audio (blue book) symbol to look at and listen tothe text.You can use the search box at the top right of the text to look for key words.

B Add backgrounds, characters and props to each frame. If you have time, convert your textunder each frame into speech by adding speech bubbles or audio to each frame.

1803 1897 1911 1932


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This is a picture of one piece of equipment that was used to find out about atoms.

J J Thomson used equipment like this to identify the negatively charged particles of theatom.These parts are found outside the nucleus of the atom.These particles are electrons.

In 1932 James Chadwick used the equipment shown below to discover particles ofatoms which were neither negatively nor positively charged.

He used this equipment to hit the element beryllium withalpha particles.The beryllium atoms gave out particles thatcame from the nucleus of the beryllium atoms.They wereneutral.They are called neutrons.There are also positively charged particles in the nucleus.They were discovered by Ernest Rutherford, and are called protons.

1 Copy and label this diagram of an atom.Choose your labels from the underlined words in the text above.

2 Which particle is negatively charged?

3 Explain how the neutron got its name.

4 ‘Hitting’ atoms with smaller particles provides information about their structure.

Suggest why.

A scientist once told a story about electrons. He said that if, after the great Floodmentioned in the Bible, Noah had started to make a necklace of electrons, threadingone electron every second for eight hours of every day, then today the chain wouldonly be two-tenths of a millimetre long. (The Flood was about 4500 years ago.)

5 What does this information tell you about the size of electrons?

cathode

magnets used todeflect electrons

phosphatecoating to showelectrons

metal plates that are electrostaticallycharged to deflect electrons

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6 Copy and complete this summary table of the particles that make up atoms.

In 1909, Ernest Rutherford carried out a seriesof experiments that changed the way that wethink about atoms.When Rutherford started his work, this was the model that scientists had of the atom.Rutherford’s assistants – Geiger and Marsden -fired alpha particles at a very thin piece of goldfoil. He found that some were slightly deflected,which was what he was expecting.What he wasnot expecting was that some of the alphaparticles actually bounced out backwards.

7 a) What charge does an alpha particle have?b) Explain why a few alpha particles were deflected backwards.c) What did this tell Rutherford about the gold atoms?d) What did this tell Rutherford about the position of the electrons in the atom?

8 Since James Chadwick’s atomic model, scientists have discovered more about atoms.Protons and neutrons are made of even smaller subatomic particles. Use the Internet tofind what the subatomic particles are. Look on www.peopleinscience.co.uk for weblinks.

Name of particle Where is it found in the atom? Charge

dense positivenucleus of atom

some alpha particles areslightly deflected

most alpha particlespass straight through

a few alpha particlesbounce backwards

positive alphaparticles

gold atom (mostly emptyspace with positive nucleus)

!

5 Inside the atom (cont.)


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Learning objectivesStudents have the opportunity to learn:� how some elements were discovered� how the discovery of new elements depends on the state of technological development.

Learning outcomesStudents:� answer questions by extracting information from the text provided (Activity 6.1)� produce a set of frames each describing the discovery of an element or group of elements

(Activity 6.1,Activity 6.2)� include information explaining what other discoveries or inventions were necessary before

certain elements could be isolated or identified (Activity 6.2).

Prior knowledgeStudents should know what elements are, and that elements have different properties. It willalso be useful if students know something about the Reactivity Series, so that they canappreciate why different extraction methods are needed for different elements. If answeringthe final question on the storyboard provided for Activity 6.1, students should know that anelement is defined by the number of protons in the nuclei of its atoms.


Background informationThere were just seven metals and a couple of non-metals, that were known to the Greeks and Arabs when the elements were thought to be Earth,Air, Fire and Water. By the timeLavoisier re-organised chemistry he could list about thirty elements, including most of thegases earlier thought to be air. Some ‘elements’ on Lavoisier’s list proved to be compounds ornon-existent, but his new system of chemistry gave chemists the incentive to discover andisolate new elements.

Many more metals were found in minerals, but it was the new techniques of electrolysis andspectroscopy that provided the most interesting discoveries during the nineteenth century.Right at the end of the century William Ramsay made the unexpected discovery of fiveunreactive gases and the Curies began the discovery of rare, radioactive elements. In the 20th

century, once the last few naturally occurring elements had been isolated, new elements weremanufactured in cyclotrons and nuclear reactors.

Activity 6.1 Discovering elements 1Students are provided with a sequence of frames showing an element (or group of elements)and the scientist that discovered them. Questions are provided to help students to extract therelevant information from the text.As an extension, students can add the symbols and dates ofdiscovery for the various elements, and print out their storyboard as a set of fact sheets. (A datasheet is included to help them with this.) If time is short, groups of students could be given oneframe each to research and complete, and their individual results combined as a class display.

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Activity 6.2 Discovering elements 2This activity is similar to Activity 6.1, but students are given only the names of the scientistsand the elements they discovered. In addition, the frames with the names of the scientists arenot given in chronological order. Students are asked to find and add the relevant information,backgrounds, characters and props, and are also asked to explain how each discovery dependedon other scientific or technological developments.They are then asked to put the elements inorder of their discovery.

Characters: Democritus/Aristotle, Priestley, Cavendish, Davy, Bunsen, Ramsay,Curie, Seaborg.

Backgrounds: Greek lyceum, Lavoisier’s laboratory or Priestley’s laboratory,laboratory in 1800s, laboratory 1900 - 1960, cyclotron.

Props: Various apparatus. General props such as bottles, books etc., may be useful.

Lesson ideas� Start by holding a brief brainstorming session to discuss how elements differ from one

another in terms of physical and chemical properties.� Ask students to speculate which elements may have been known about in ancient times.

If students have already studied the Reactivity Series, this is a good opportunity to linkreactivity with ease of extraction.

� Following the lesson, ask students to suggest why some elements were discovered beforeothers. Students should realise that the isolation of some elements depends on quitecomplex technology (e.g. distillation of liquid air) which has only been developed in thelast couple of centuries.

� It is worth stressing that new elements cannot be made by chemical reactions, but aremade by smashing particles together in a cyclotron to add protons or neutrons to nuclei.

8 a) Mendelevium was named after Mendeleev.Nobelium was named after Alfred Nobel Lawrencium was named after Ernest Lawrence (an American physicist who worked on high-energy physics). Rutherfordium was namedafter Rutherford. Dubnium was named after Dubna in Russia (where it was made for the first time). Seaborgium was named after Seaborg. Bohrium was named after Bohr. This informationcan be found at www.chemicalelements.com or www.webelements.com. The number is the isotope number of each element.

b) Once again www.webelements.com provides information on these elements.Other links can be found on the People in Science website.

1 Suitable pie chart or bar chart.

2 Sulfur – S, potassium – K, phosphorus – P, calcium – Ca, nitrogen – N, hydrogen – H, carbon – C, oxygen – O.

3 Poem.

4 Gold – 79, Lead – 82.

5 A nuclear reaction involveschanging the nucleus of theatom, a chemical reactioninvolves only the electrons.

6 Gold is more valuable than leadso they would become rich.

7 It would not be worthwhilebecause it would cost more tomake the gold than it would be worth.





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Today, scientists know of about 115 elements. In ancient times only a few elements wereknown, although people did not call them elements then. Some elements can only beextracted (obtained from their compounds) by using electricity, and some elements are actually made in nuclear reactors.These elements could not be discovered until electricity had been discovered or nuclear reactors had been invented.

6.1 Discovering elements 1A Open storyboard ‘Activity 6.1’.The storyboard shows you some of

the scientists who discovered new elements, and the names of theelements that they discovered.Answer the questions to explain howthe different elements were discovered. Use the text window tohelp you.To look at the text click on the text/audio symbol(blue book).You can use the search box at the top right of the text to look for key words.

B Add suitable props to the scenes.Add a text box to eachscreen to show the modern symbols for the elements.If you can, include the date that each element wasdiscovered.You will need to use the data sheet that goes with this activity to help you with this.

C Print out your storyboard as a set of fact sheets.

6.2 Discovering elements 2A Open storyboard ‘Activity 6.2’.The storyboard has a

set of blank frames giving the names of someelements and the name of the scientists who discovered them.Use the text provided (by clicking on the blue text/audio symbol) to find out about the discovery of these elements.Add text in the caption window todescribe how each element was discovered.You can use the search box at the top right of the text window to look for key words.

B Add suitable backgrounds, characters and props to the scenes. Some of the elements in this activity could not have been discovered until a certain piece of apparatus had been invented, or some other scientific discovery had been made. Include the props that were necessary for each element, and a brief explanation for each one.(Hint: look at the last frame of this activity.)

C Add a text box to each screen to show the modern symbols for the elements. If you can, include the date that each element was discovered.You will need to use the data sheet that goes with this activity to help you with this.Re-arrange the frames into the order in which the elements were discovered.




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We are made of many different elements.

1 Draw a pie chart or a bar chart to show this information. Make it colourful and eye catching.

2 Each element has a symbol.Write these symbols on your diagram.

3 Write a cinquaine about one of the elements in the table.A cinquaine is a five line poem:� the first line is one word and would name the element� the second line has two words and describes the first line� the third line has three words and tells what the first line is doing� the fourth line has four words and tells how the writer feels about the first line� the fifth line renames the first line in a single word.

Here is an example of a cinquaine.OxygenLavoisier discoveredRelights glowing splintLife depends on itAcid-former

other elements = 200 g

sulfur = 125 g

potassium = 175 g

phosphorus = 500 g

calcium = 1 kg

nitrogen = 1.5 kg

hydrogen = 5 kg

carbon = 9 kg

oxygen = 32.5 kg

Human being

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The alchemists kept trying to turn lead into gold, but they did not succeed. In 1972scientists in Russia opened up the lead shielding of their experimental nuclear reactoronly to find that a thin part of the inner surface of the lead shield had turned to gold.How was this possible?

Alchemists performed chemical reactions as part of their work. In a chemical reactionthe electrons in the outer shells of an atom may be gained, lost or shared with anotheratom. Chemical reactions do not affect the nucleus of an atom.The number of protonsin the nucleus of an atom defines which element the atom belongs to.The only way tochange one element into another is to change the number of protons in the nucleus.This can only be done in a nuclear reaction. Nuclear reactions happen when elementsare bombarded with small particles like protons.These reactions take place in large,expensive pieces of equipment like nuclear reactors or cyclotrons and only a very smallamount of a new element is formed each time.

4 Find out how many protons there are in the nuclei of gold atoms and of lead atoms.

5 Explain in your own words the difference between a nuclear and a chemical reaction.

6 Why do you think the alchemists wanted to turn lead into gold?

7 We could now produce gold from lead. Explain why this would not be worth doing.

This table gives information on elements 101 to 107

8 a) Pick 4 elements from this table and find out:What or who they were named after and what the number after their name means.A chemistry textbook will have many of the answers.

b) Elements 110 to 118 have yet to be given official names. Do some research on one ofthem and decide on a name for it. Explain what made you choose the name.You will find some useful weblinks at www.peopleinscience.co.uk

Atomic number Symbol Isotope

101 Md mendelevium 258102 No nobelium 259103 Lr lawrencium 262104 Rf rutherfordium 261105 Db dubnium 262106 Sg seaborgium 266107 Bh bohrium 267

6 Discovering elements (cont.)


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Atomic Element Symbol Relative DateNumber of atomic of

element mass discovery

1 hydrogen H 1 17662 helium He 4 1868/18953 lithium Li 7 18184 beryllium Be 9 17985 boron B 11 1808

6 carbon C 12– diamond ancient– graphite ancient

7 nitrogen N 14 17728 oxygen O 16 17749 fluorine F 19 188710 neon Ne 20 189811 sodium Na 23 180712 magnesium Mg 24 180813 aluminium Al 27 182714 silicon Si 28 1824

15 phosphorus P 31 1669(white)

16 sulphur S 32 ancient(monoclinic)

17 chlorine Cl 35.5 177418 argon Ar 40 189419 potassium K 39 180720 calcium Ca 40 180821 scandium Sc 45 187922 titanium Ti 48 182523 vanadium V 51 183024 chromium Cr 52 179725 manganese Mn 55 177426 iron Fe 56 ancient27 cobalt Co 59 173528 nickel Ni 59 175129 copper Cu 64 ancient30 zinc Zn 65 174631 gallium Ga 70 187532 germanium Ge 73 188633 arsenic As 75 125034 selenium Se 79 181735 bromine Br 80 182636 krypton Kr 84 189837 rubidium Rb 86 1861

Atomic Element Symbol Relative DateNumber of atomic of

element mass discovery

38 strontium Sr 88 180839 yttrium Y 89 184340 zirconium Zr 91 182441 niobium Nb 93 180242 molybdenum Mo 96 177843 technetium Tc 99 193744 ruthenium Ru 101 184445 rhodium Rh 103 180346 palladium Pd 106 180347 silver Ag 108 ancient48 cadmium Cd 112 181749 indium In 115 186350 tin Sn 119 ancient51 antimony Sb 122 ancient52 tellurium Te 128 178353 iodine I 127 181154 xenon Xe 131 189855 caesium Cs 133 186056 barium Ba 137 180857 lanthanum La 139 183972 hafnium Hf 179 192373 tantalum Ta 181 180274 tungsten W 184 178375 rhenium Re 186 192576 osmium Os 190 180377 iridium Ir 192 180378 platinum Pt 195 173579 gold Au 197 ancient80 mercury Hg 201 ancient81 thallium Tl 204 186182 lead Pb 207 ancient83 bismuth Bi 209 175384 polonium Po 210 189885 astatine At 210 194086 radon Rn 222 190087 francium Fr 223 193988 radium Ra 226 189889 actinium Ac 227 189990 thorium Th 232 182891 protactinium Pa 231 191792 uranium U 238 1841

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Learning objectivesStudents have the opportunity to learn:� different ways in which radioactive materials are used� some of the arguments for and against the use of radioactive materials in medicine.

Learning outcomesStudents:� summarise facts about radioactive materials and some of their uses (Activity 7.1)� produce a simple explanation of some of the ways radioactive materials are used in the

diagnosis and treatment of diseases (Activity 7.2)� outline arguments for and against the use of radioactive materials from the text provided,

and add their own opinions and conclusions (Activity 7.3).

Prior knowledgeStudents should know something about radioactivity and its dangers.


Background informationFrom the time that the Curies discovered radium it was thought that radiation would havebeneficial uses in medicine.The dangers of exposure to high levels of radiation were onlyslowly recognised.There are beneficial uses for many radioactive isotopes, such as iodine indiagnosing thyroid ailments, caesium in cancer treatments and technetium as an all-purposemedical tracer.The dangers of using radioactive tracers in medical treatments focus mainly on their disposal.

The balance between the risks and the benefits of radioactive materials and radiation has beenat the root of many environmental and health concerns.

Activity 7.1 Radioactivity and its usesStudents are asked to produce a short series of ‘video clips’ to be added to a CD-ROM,briefly explaining what radioactive materials are, and how they can be used in medicine.Pupils are then asked to explore some of the wider uses of radioactivity. They will need accessto textbooks or the internet to do this. Suitable weblinks can be found on the People in Sciencewebsite.

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Activity 7.2 Radiation and youStudents are asked to make a short video to explain to patients how and why radioactivesubstances are used in hospitals.

Activity 7.3 Radioactivity – for or against?Students are asked to add text or speech to a TV debate on whether or not radioactivematerials should be used. Most information can be extracted from the text provided, butstudents are also encouraged to add frames explaining their own ideas, and to give their ownopinion at the end.

Characters: Curie, Seaborg, Dr Patel, Dr Banning, Parsons, Procter,other modern characters.

Backgrounds: laboratory 1900 - 1960, cyclotron, hospital exterior and interior,nuclear fuel dump,TV studio.

Props: General props such as bottles, books etc., may be useful.

Lesson ideas� Start by brainstorming students’ ideas about radioactivity, what it is and what it can be

used for.� Ask students for their opinions on the safety of using radioactive materials for power

generation and in hospitals.� Plenary discussions will depend on which activities students have carried out.They could

be asked whether any of their opinions have changed as a result of the activities.Pupils could then be asked to write an essay presenting the case for and against the use of radioactivity.This may be useful for their GCSE English portfolio.

1 15%.

2 Pie chart.

3 82%.

4 1898.

5 Pierre Curie found that radium could beused to treat tumours.

6 Radium was inserted into the ears inneedles, drunk as water that had beenexposed to radium or worn in corsets.

7 Radium was a naturally occurringsubstance so people thought that it was safe.

8 A patent is a licence giving someonethe right to be the only person toproduce or sell an invention.

9 The Curies did not patent radiumtherapy – which would have made them a lot of money because it was very popular.

10 Letter or poster.





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Some substances are naturally radioactive, and we get some radiation from these all the time.Today, scientists, engineers and doctors use radioactive materials for generating power, inresearch and to diagnose and treat patients.We all get some radiation from these sources, too.

7.1 Radioactivity and its usesMake a set of short video clips to be put onto a CD-ROM explaining science to teenagers.

A Open storyboard ‘Activity 7.1’.The storyboard shows you four people who havesomething to explain about radioactive substances.Answer the questions under each frame.Use the text provided in the text window to help you.The text can be viewed when youclick on the blue text/audio button.You can use the search box at the top right of the textto look for key words.

B Add suitable props to the scenes.Add speech bubbles or audio to make each personexplain their thoughts and ideas in their own words, or record your own audio.Add extraframes if you need to.

C Find out how radioactivity is used in industry and to generate electricity.You will need touse textbooks or the internet to help you do this.

7.2 Radiation and youRadioactive substances are often used in hospitalsto diagnose or treat diseases. Many people areanxious about radiation, and doctors need toexplain how and why radioactive substances willbe used. Make a short video that could be shownto patients to help them understand whyradioactive substances are used.

A Open storyboard ‘Activity 7.2’.Add moreframes so that Dr Patel can explain whatradioactive substances are used for.You mayalso need to use some words from Dr SandraBanning or from Bill Parsons.

B Add suitable props to the scenes.Add speechbubbles or audio to make each person explainin their own words, or record your ownaudio.Add extra frames if you need to.

7.3 Radioactivity – for or against?Some people think that the advantages of using radioactive substances outweigh the possiblerisks from radioactivity. Other people think that radioactive substances should not be used at all.Make a storyboard to show a TV programme that discusses these different points of view.

A Open storyboard ‘Activity 7.3’.The storyboard shows you some people who are in favourof using radioactive substances, and someone who is against their use.Answer the questionsunder each frame to explain each person’s opinions.

B Can you think of any other reasons for or against using radioactive materials? Explain yourideas by adding a new frame and a new character.

C Add a final frame to explain what you think about the use of radioactive substances.Explain the reasons for your opinion.

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Source of radiation Average dose per year (%)

Radon 55%Medical ?Space and the Earth 27%Man-made products e.g. smoke alarms 2%Other e.g. Nuclear waste 1%

We are constantly exposed to natural radiation from space and from some kinds of rocks.Most of the natural radiation comes from radon. Radon is a radioactive gas that is common insome parts of the country – usually where there is a lot of granite rock. Some radiation doesnot come from natural sources. Look at this data:

1 Work out what percentage of our average radioactivity dose comes from medical sources.

2 Plot the data in the table as a pie chart.

3 How much of our average dose of radioactivity comes from natural sources?

Read this passage:

When radium was discovered in 1898 it attracted a lot ofinterest because of its medical uses. Pierre Curie studied theeffects of radium on animals, and found that by destroyingdiseased cells it could offer a treatment for growths, tumoursand certain forms of cancer.This therapeutic method was calledCurietherapy or radium therapy.

Radium therapy became very popular in about 1915. It was used to treat a wide variety of diseases including rheumatism, anaemia,epilepsy and ringworm. Radium was given to patients in several ways– it could be injected or, in the case of ear infections, it was insertedas needles in the ears that were then left for three weeks.Radium was also sewn into corsets to help treat arthritis in olderwomen. One of the most popular ways of taking radium therapy wasto drink radium water. Radium water was made by storing water ina jar that had a disc of radium in it.The water was left for a month and then drunk.

Radium therapy was seen as natural because radioactivity occursnaturally in the world.This meant that people thought that theycould drink as much radium water as they liked.The practice onlystopped in 1932 when an American millionaire died of radiumpoisoning. He had drunk 1400 bottles of radium water in two years.Thirty-five years after his death his skeleton was still radioactive!

Radium therapy was so popular that huge amounts of radiumwere needed.The Curies could have patented their technique forproducing radium but they didn’t. Marie Curie gave a gram ofradium worth a million gold francs to her laboratory in 1906.

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4 When did Marie Curie discover radium?

5 Why did Pierre Curie think that radium could be used to treat diseases?

6 How was radium given to patients?

7 Why did people think that radium was safe?

8 Find out what patented means.

9 Einstein said that Marie Curie had not been corrupted by fame. Suggest what he meantby this. Use information from the passage above to explain your answer.

Lavinia Greenlaw wrote a poem called The Innocence of Radium. It was about womenwho painted the dials on watches.The watches were painted with radioactive materialsso they glowed in the dark.This is one line from the poem:

‘For a joke she painted her teeth and nails,‘jumped out on the other girls walking home.’

10 Write to a letter to the girls explaining why radioactivity today is both dangerous andhelpful. Make sure that you explain both sides of the argument.OR Design a poster to advertise the medical uses of radium in the 1920s.

7 Using radioactive materials (cont.)


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This section outlines other activities that could be carried out using the text, characters andbackgrounds supplied with Elements and Atoms.

Alchemy and chemistryAsk students to develop a storyboard explaining the difference between alchemy andchemistry, and to explain what modern chemistry gained from the alchemists.

The aim of alchemy was to find the philosopher’s stone, which would turn base metals intogold, and also to discover the elixir of life, which would give eternal youth.The alchemistsdeveloped many techniques that are still used in modern chemistry, but their procedures werealso bound up in mysticism and ritual. Modern chemistry aims to find out about elements andtheir interactions by experiment and observation.

Characters: Jabir, Rhazes, Bacon, Paracelsus, Boyle.

The story of air and gasesAsk students to find out the different ideas people have held about air, and how different gaseswere discovered.

Ideas about the nature of air changed from the old idea that Air was one of the four elementsthat made up everything, to Stahl’s notion that air absorbed phlogiston from burningsubstances, and then to air as a mixture of gases.The story continues as far as Ramsay’sdiscovery of the noble gases.

Characters: Aristotle, Stahl, Priestley, Cavendish, Lavoisier, Berzelius, Ramsay.

Time lineAsk students to use the characters to put together a timeline to illustrate how ideas aboutatoms have changed from the time of the Greeks through to our modern-day ideas. Eachgroup could be asked to do one character and they could then be put together as class display.

Characters: All except modern characters.


QUICK-START GU

IDEE

lements and A

toms


2.A

dding a Backgro

und

Click on the green

arrows to toggle

between selections

of backgrounds

Click on the blue

Backgrounds tab to see six backgrounds at a tim

e.C

lick again to see 12 at once

Create copies of props by

pressing Ctrl,keeping it pressed

and clicking on the prop you wish

to copy.Drag to a new

position

To load your own digital im

age as abackground,click on the orangefolder icon and choose an im

age filefrom

your hard-disk or network drive

1.A

dding Text

Choose

characters byclicking onthem

anddragging anddropping theminto the‘C

omposition’

window

Click on this green Q

uickPalette tab to see fourcharacters at a tim

e.Click

again to see 16 at once

To delete acharacter drag itinto the orangew

aste-paper bin

To move a character,just

click on it and drag it toa new

location in theC

omposition w

indow

4.A

dding Pro

ps

Click on the orange

Props tab to see fourprops at a tim

e.Click

again to see 16 at once

Click on the green up

and down arrow

s tom

ove through theselection of props

3.A

dding Characters

First,click on thegreen C

omposition

tab.Next,choose a

background byclicking

on the blueBackgrounds

tab an

dselecting one thatsuits the scene youare building.It w

illautom

atically loadinto the C

omposition

Window

.

The

Com

positionW

indow

Cho

ose fro

ma largeselectio

n of

props by

clicking on

the orange

‘Props’ tab.

Drag in to

theco

mpo

sition

window

Click on the

orange folderto load in yourow

n text

Select a piece oftext and drag anddrop into thecaption w

indow

Type in a word and

press the Search iconto find references to it w

ithin the text

Use the scroll bar to

move to the relevant

part of the text

Click on the

blue Text andA

udio tab tosee and hearthe full text ofthe library


QUIC

K-ST

ART

GUID

EE

lem

ents

and

Ato

ms


Sele

ct t

hech

arac

ter

orpr

op a

nd r

ight

clic

k to

ope

nth

e M

anip

ulat

or.

6.B

uild

ing

Lay

ers

5.R

ota

te,P

ose

,Lay

er a

nd S

cale

cha

ract

ers

and

pro

ps

Sele

ct a

char

acte

r th

encl

ick

on t

hesp

eech

or

thou

ght

butt

ons

to t

ype

in w

hat

is be

ing

said

or

thou

ght.

8.A

ddin

g a

Pre

-rec

ord

ed A

udio

File

Rot

ate

the

char

acte

r or

prop

by

clic

king

on t

he le

ft or

righ

t ar

row

sne

xt t

o th

ero

tate

key

Cha

nge

the

size

of t

he c

hara

cter

or p

rop

bycl

icki

ng a

nddr

aggi

ng u

p an

ddo

wn

on t

hesc

ale

key

Pose

the

char

acte

r or

prop

by

clic

king

on t

he le

ft or

righ

t ar

row

sne

xt t

o th

ePo

se k

ey

Mov

e th

e ch

arac

ter

or p

rop

infro

nt o

r be

hind

oth

er o

bjec

tsby

clic

king

on

the

left

or r

ight

arro

ws

next

to

the

Laye

rs k

ey

Cho

ose

the

red

Laye

rs t

ab t

om

ove

elem

ents

in t

heC

ompo

sitio

nW

indo

w in

fron

t or

beh

ind

each

oth

er a

ndto

acc

ess

the

‘spec

ial e

ffect

s’m

enu

for

each

elem

ent

in t

hepi

ctur

e.

Clic

k on

the

blu

e ta

b on

each

laye

r to

acc

ess

its‘sp

ecia

l effe

cts’

men

u

To la

yer

any

elem

ent

in fr

ont

or b

ehin

dan

othe

r,cl

ick

on it

s im

age

and

drag

itup

or

dow

n re

lativ

e to

oth

er e

lem

ents

Mov

e a

bubb

le

by c

licki

ng a

nddr

aggi

ng t

he t

oped

ge o

f the

bub

ble

Res

ize

a bu

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by

clic

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and

dra

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the

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of t

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ubbl

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Clic

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the

tex

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to

add

a te

xt b

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oyo

ur fr

ame

Mov

e th

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inte

r by

clic

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and

drag

ging

Clic

k on

the

spe

aker

icon

once

to

star

t pl

ayin

g th

eau

dio

file

and

agai

n to

sto

p

Clic

k on

the

spe

aker

icon

in

the

fram

e’s

thum

bnai

l to

hea

r th

e fil

e th

at h

as

been

att

ache

d

Thu

mbn

ail

Ope

n A

udio

con

trol

s

To a

dd a

pre-

reco

rded

audi

o fil

e,fir

st,

clic

k on

the

blue

Tex

t an

dA

udio

tab

the

ndr

ag a

spe

aker

icon

to

the

thum

bnai

l of

the

fram

e.A

spe

aker

icon

will

app

ear

tosh

ow t

hat

itha

s be

enat

tach

ed.

7.A

ddin

g S

peec

h an

d T

houg

ht B

ubbl

es

Clic

k th

e la

rge

red

cros

s to

clo

se t

heM

anip

ulat

or C

lick

on t

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mal

l red

but

ton

to d

elet

e th

e ch

arac

ter

or p

rop


QUICK-START GU

IDEE

lements and A

toms


10.S

aving and Lo

ading Sto

ryboards

Click on the red

Utilities tab.

Here you can

save and loadstoryboards.Storyboards canbe saved fromany of thescreens usingthe save buttonin the top left ofthe screen

To create a new,

blank storyboard,click on the N

ewStoryboard icon

To play back a previously createdstory board,clickon the Load button

Autosave w

illautom

aticallysave yourstoryboard atset intervals

Click on the

'save .K2 file'

to save yourstoryboard as aK

ar2ouche file

Click on the

'save movie' button

to save yourstoryboard as aQ

uickTim

e movie

Click on the

green printericon to print

Return to the

templates selection

page by clicking onthe back icon

Any text in the

caption window

will

also appear in theprinted docum

ent

Discard fram

es fromthe print tem

plate bydragging them

intothe red w

aste bin

To access specialeffects,click on thegreen C

omposition

tab to return to theC

omposition W

indowand click on the redLayers tab.N

ext,clickon the blue tabassociated w

ith theelem

ent you wish to

add the specialeffect to.

Scroll through the differentelem

ents using thegreen arrow

button

Undo any special

effects you haveadded by clicking on the reset button

Changing

the colourcan help tocapture them

ood of the scene

Change the

transparency of acharacter to create‘ghostly’ effects

Blur the background w

ith the sharpness settingand create a cinem

atic‘depth of field’ effect

9.P

laying the Frame

Stop or pause thefram

e during play backby clicking on the stopor pause buttons

Click on the

Cycle icon for

continuouslooping playback

Click on the Full Screen toggle button to

see the frame show

n as a full screen when

it is played back.Click again to view

playback in the Presentation W

indow C

lick on the orangePresentation tab toaccess the Presentationscreen.

Click the Play button to

see your frame show

nin the presentationw

indow,A

ny attachedaudio files w

ill beplayed back.

First,click on the orangePrint button.N

ext,choose an orientationoption by pressingon the portrait orlandscape icons.Finally,select one ofthe layouts and dragfram

es of your storyboard into the boxes

12.S

pecial Effects

11.P

rinting Sto

ryboards


QUIC

K-ST

ART

GUID

EE

lem

ents

and

Ato

ms


Use

the

se

cont

rols

to

reco

rd y

our

own

audi

o fil

es.

14.

Add

ing

Mul

tipl

e A

udio

File

s

16.

Set

ting

yo

ur o

wn

Opt

ions

15

.R

eco

rdin

g yo

ur o

wn

Aud

io F

ile

To p

erso

nalis

e yo

urse

ttin

gs,f

irst

,cl

ick

onth

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tiliti

es t

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t,cl

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een

optio

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utto

n.To

mak

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ange

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eed

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apa

ssw

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def

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.

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e bl

ue T

ext

and

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t,cl

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but

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Scri

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w.

Dra

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Scr

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Scrip

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Tim

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Cha

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by c

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nddr

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n th

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of t

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Clic

k on

the

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wth

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Clic

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the

ora

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fold

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file

sth

at y

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prev

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Clic

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the

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