%~ ..~~.

The Commonwealth of The Bahamas

Bahamas General Certificate of Secondary Education

CHEMISTRY SYLLABUS.

Testing &.Evaluat;ion SectionMinistry of Education

First printed 1993

Reprinted 2003

'.'~"I"'-4ll

I

,.~

rrABLE OF CONTENTS

iNTRODUCTION

AIMS

ASSESSMENT OBJECTIVES

SCHEME OF ASSESSMENT

,"

COURSE CONTENT

TEClillIQUES OF ASSESSMENT

INTERNAL ASSESSMENT OFPRACTICAL SKILLS

MATHilV\TICAL REQUIREMENTS

GLOSSARY OF TERMS

GRADE DESCRIPTIONS

APPENDIX A.

PERIODIC TABLE

RECOMMENDED TEXTS

PAGE

1

2

4

7

10

33

35

16

47

50

54

55A

55B

-1-

THE BAHAMAS GENERAL CERTIFICATE

OF

SECONDARY EDUCATION

1_ INTRODUCTION

The information cont~ined in this syllabus, is intended to definethe minimum requirements for preparing candidates for the BahamasGeneral Certificate of Secondary Education (BGCSR) ChemistryExamination.

The BGCSE Chemistry Examination is intended for students aged 16+who have completed a course which satisfies the requirements orthe syllabus.

1 The Scheme. of Assessment is designed to assess the positive; achievement of candidates of differing abilities.

The standard of the Examination will be equivalent to that of theG.C.E. 'Q' level examinations, but is designed tQ providecertification for a larger population of students, ~nd a graderange of A-G.

Through this examination candidates are being offered successthrough performance within their own ability range.

The Examination syllabus allows for the implementation of variedmethods of instruction and assessment while helping the candidateto develop the skills and understanding needed to derive maximumbenefit from the subject content.

Coverage of the subject content is intended for a period ofapproximately'three (3) years, beginning in grade 10. TheExamination includes written components and a practicalcomponent. The guidance offered through the syllabus is intendedto enhance the performance of student and teacher alike.

-2-

AIMS

The Aims listed below include references to certain attributesand qualities which cannot and should not be assessed throughformal examinations, but which do. form an essential part of theChemistry course. In thi~re~~ect th~Aim~differ from theAssessment Objectives which all refer to qualities andcompetencies that can be assessed. These Aims are not listed Inorder of priority.

1.

2 .

3 .

5 .

. 6.

7 .

To stimulate and sustain curiosity, interest and enjoymentof the .,environment through studying Cl)emistry and itsapplications.

To develop an appreciation of the scientific, social,economic, environmental and technological contributions andapplications of Chemistry.

To show that Chemistry is a coherent framework of knowledgebased 'on fundamental theories of the structure andpossesses of the Chemical world.

To foster the development of skills needed to betterunderstand local technological advances and to pursuetechnologically oriented careers.

To develop techniques for solving problems throughexperiments, following a scientific approach by developingthe skills of observation, experimentation, proc~ssing andinterpretation of data, evaluation of evidence, recordingand formulation of generalization and models.

To ensure that students can follow instructions inclUdingthose relevant to complying with safety procedures.

To provide suitable knowledge, understanding and skills forstudents who wish to qualify for entry to fields of studyor job training programmes that require a generalunderstanding of Chemistry.

-]-

8. To foster the development of relevant skills £orcommunication, imprpvi9ation and for working along withothers.

9. To encourage students to apply, qualitatively andquantitatively, their kno~ledge and understanding ofchemical principles to familiar and unfamiliar situations.

10. To encourage students to appreciate the developing andsometi~es transitory nature of chemical knowledge,principles and models.

-4-

3. ASSESSMENT OBJECTIVES

CLUSTER OF ASSESSMENTOBJECTIVES

KNOWLEDGE WITHUNDERSTANDING

ASSESSMENT OBJECTIVES

Candidates should be able

to show knowl~dqe andunderstanding of scientific:

~•....

TARGETWEIGlITING

40%

~.{r

3.1 phenomena, facts,laws,definitions, concepts,theories, principles,models and generalizations.

3.2 vocabulary, terminology,conventions, symbols andunits.

3.3 instructions and apparatus,including techniques ofoperation and aspects ofsafety.

3.4 methods of measurements ofquantities and theirappropriate units.

3.5 applications to technologyaffecting social, economicand environmental issues.

J.6 explanations of familiarfacts, observations andphenomena in terms of laws,th~ories an~models.

HANDLINGINFORMATION ANDPROBLEM SOLVING

3.7

3.8

3.9

3.10

Candidates should be able todefuonstrate skills and ability to:

translate informationfrom one form to another;

use and interpret formulae;

communicate observations,ideas and argumentslogically, concisely andin appropriate form;

make decisions and formulateconclusions based onexamination of evidence andobservations;

40%

CLUS~ 9FASSESSMENT...OBJECTIVES

-5-

ASSESSMENTOBJEcrIVES TARGETWEIGHTING

HANDLINGINFORMATIONl\ND·PROBLEMSOLVING(CONTtD)

3.11

3.12

3.13

3.14

3.15

3.16

select appropriat~ facts toillustrate a-given principle,concept, law,. theory, mode 1 orpattern;

relate sciehtific principlesto everyday situations;explain andevalu~tetechDo~ogical applicationsof ChemIstry and theira~sociated ~ocial economicand environmentalimplications;

stigge~t s6ientificexplanations of unfamiliarfacts,obserV~tions aridphenomena;

apply scientific concepts andmethods to solve problems,including appropriatecalculations;

solve problems bydesigning, conductingand interpreting theresults of simpleexperiments;

recognize that data frompractical work is subjectto various limitations.

CLUS~O~ASSES~OBJECTIVES

EXPERIMENTALSKILLS ANDINVESTIGATIONS

3.17

3.18

3.19

3.20

-6-

.1\SSESS~OBJECTIvES

Candidates should be able to;

£ollowand cArry outpracti~al instrtictionsaccurately and safely;

observe, measure and recordaccurately and systematically;

recognize mistakes,misconceptions~ unreliabledata and assumptions;

select appropriateapparatus or materialsnecessary to achieve giventasks;

TARGET .WEIGHTING·

20%

3.21 devise experiments for a statedpurpose.

4 _ SCH~E OP ASSESSMENT

The Examination will comprise of written papers and apracticalcqmponent.

The design of the examination will allow candidates 6fa wide ability range to demQm::trate what they know,understand and can do ..

4_1 Dlfferentlatian

The purpose of this differentiated scheme of assessment,by using" components that are designed to test particularparts of the ability range, is to examine candidates atlevels at which they' can demonstrate achievement and providepositive evidence of attainment.

It follows that if .candidates are to obtain benefit fromtaking papers designed to meet their particular needs,centres must take care to ensure that each candidate is

entered for the combination of papers for which he or sheis most suited.

The scheme of assessment, relative to the BGCSE Chemistry 1Sas follows:

There will be three written papers available and a practicalassessment, of which papers 1, 2 and the practical assessmentwill be ~ompulsory.

(i) Candidates will be awarded Grades C to G on the basisof their performance in components 1 and 2 together withthe Practical Assessment.

(ii) Candidates who achieve a Grade C or D on the basisof their performance in (i) above and a Grade A or Bmark on the optional ext~rision paper will be awardedGrade A or B respectively. Internal Assessment willplay an appropriate part in the award of Grades A and B.

-8-

SUMPtARY OF ASSESSKEN'T.

COMPONENT DURATION TITLE PERCENTAGE. ··WEI GHTING

1

2 .

3 .

4

1 1/4 hour

1 1/2 hour

1 1/4 hour

Paper 1(Multiple choice).

Paper 2(Structured andshoit answer).

·Paper 3(Structured andftee response).·

Practical Assessment.

30%

50%

20%

PAPER 1

PAPER 2

PAPER 3

COMPONENT 4:

This will consist 6f SO multiple-choicequestions of the four (4) choice tyPe.

This will consist of structured and shortanswer questions .. Candidates will berequired to .answer all questions~

This will comprise structured questions andfree response questions. The Paper will bedivided into two (2) sections.

section A will consist of a number of compulsorystructured questions.

SectionB will consist of a nwnber of free­response questions allowing candidates somechoice ..

Internal Assessment of Practical Work.

-9-

SUHMARY .OF ASSESSMENT WEIGHTIRGAND J\QARnTNGOF GRADES

For the award of grades e, D, E, F, G.

COMPONENT DURATION DESCRIPTION PERCENTAGE. WEI GIITING

1 (Paper 1) 1 1/4 hour

2 (Paper 2) 1 1/2 hour

4

50 multiple choice (4

option) questi9ns.

Structured and shortanswer questions.

Internal Assessmentof Practical Work

30%

50%

20%

For the award of Grade A, B proViding grade C or D has beenachieved in components 1, 2 and 4.

COMPONENT DURATION DESCRIPTION PERCENTAGEWEIGHTING

3 (Paper 3) 1 1/4 hour

4

Struct~red questionsand free-responsequestions.

Section A - CompulsoryQuestions.

Section B - FreeResponse.

Internal Assessmentof Practical Work.

40%

40%

20%

-1.0-

s. CHEMISTRY COURSE. CONTENT" '

The content as set out below does not provide ateachirtgorder;,.It does, however, represent the topics On ~hi~h the cindidatewill be assessed.

"l.'OPICS

5.1 Applications and Implications of Chemistry

The syllabus content shOuld b~covered in such a way'so asto draw attention to the industrial, social, economic,environmental and technological aspects of Chemistry whererelevant.' ,

ref: - Mineral arid energy resources-·~ollutionc. ontrol- Adequate/iilcidequate world food supply- Beneficial and~antisocial effects of Chemistry

Because of the novel nature of this ai~a of the syllabus,which should be included in the teaching of sections 5.2 to5.12, more details have been given in section 5.13.

5.2 Techniques of Chemistry

2.12.22.3

Separation of mixtures and purification'Test for purityMeasurement

, 5.3 Nature of Matter

3.1 Kinetic Theory3.2 Elements and Compounds3.3 Atomic Structure3.4 Bonding

5.4 The Mole Concept

5.5 Aciids, Bases and Salts

5.1 Properties of Acids, Base and Salts.5.2 Identification of Ions

5.6 Energy changes in Chemical Reactions

6;1

Heat energy6.2

Electrical

5.7

Speed of Reaction

5.8

Redox Reactions

~Ll-

5.9 The Periodic T~le

9.1 periodic trends9.2 Group trends and characteristics

5.10 Metals

10.110.2.10.3

.Properties of MetalsReactivity Series~xtraction of Metals

5.11 Non-Metals

11.111.211. 311.411.511. 6

HydrogenOxygenNitrogensulphurChlorineCarbon

5.12. Organic Chemistry

5.13. Social,< Economic, Environmental and Technologicalapplications of Chemistry.

13.113.213.313.4

Mineral and Energy SourcesPollutionFood SupplyUse and abuse of chemicals

'-J2-

COURSE CON1'E:NT

The first column contains the Topic. The second columncontains specific concepts and principles that are compulsory forall candidates which are titled Core Content.

The third column contains ~dditional concepts and principlesrequired to obtain grades A or B which are titled ExtendedContent.

IITOPIC

ICORE CONTENT I EXTENDED CONTENT

II

II

2.

TECHNIQUES OF OIEMISTRY III

II

II

I2.1 SEPARATION OF MIXTURE

I Solution,Ifractional

.~'

AND PURIFICATION I crystallization,I distillation

Idistillation, I

Ifiltration, I

I centrifuging,

II

decantation, and II paper chromatography.

II

II

I2.2 TEST FOR PURITY

I Melting points,II boiling points.

II

II

II

I2 . 3 MEASUREMENT

I The measurement ofII mass,

temperature,I'1 volume, time and

II

length, using II

appropriate apparatus. II

II

I

-J.3-

IITOPIC

ICORE CONTENTIEXTENOED CONTENT

II

II

3 _ TIll! NATURE OF MATTERII

II

J.1K UleTIC TllEORY Il.The Piu-Uculate IEla~;Lic r:olJ.isloll

INLlI.Ul"C of MaLLerI

II

I

w

II

2 _Temperature and II

its relationship tal

Ienergy and motion.I

II

II

I

J _Diffusion. IBrownian motion.

I

Evidence for theI1\.nexperimentto

Imovement of Iillustrate

Iparticles in IBrOWllian motion.

Iliquids and gases.I

II

II

I4.The particle I

Ipacking of the I

Ithree physical I

Istates of matter.I

II

II

~ I5. Terms related La II

changes of state.I

II

II

I

I

I6. A diagram relating I

Ithe physical I

Ichanges of state.I

II

ISOLID ~ LIQUIDI

I \;f II

II

GI\S II

II

I

-1-4-

I

ITOPIC

{CORE. CONTiiliT\EXTENDED CONTENT

I\

II

KltffiTICTHEORY CONT'D\7. Given any number \..Phrases "directly

Iof gases and theirIproportibnill" and

Irelative masses I. 11 inversely

Ilist them in order,Iproportional".

Iof their·rate ofI

r

diffusion. II

IMathematical forms

IIof Charles Law and

IIBoyle's Law.

\

\

I8. Quali tati 'le ICharles and

Itreatment IBoyle's laws

1

of the effect 1combined.

Ithat temperature I

Iwill have on theI

Ivolume of a gas.I

II

1

II

9. Qualitative IProblems involvingI

treatment Ithe combined Laws

Iof the effect Igiven the factors

Ithat pressure willIand calculate for

Ihave on a gas. Ithe unknown.(Only

\j

IIsimple numbers to\ IIbe used).

II

II

\ 10.The conditions forI

Ir.t.p.and s.t.p.I

II

II

II

U· ._.

II

3 .2 ELEMENTS AND COMPOUNDS I1. The differenceI

Ibetween elements I

Iand compounds. I

\

1

II

I2. The molecule. I

II

II

II

'-1-5-

I

ITOPIC

ICORE CONTEN'I'IEXTENDED CONTENT

II

II

3.3 ATOMIC STRUCTURE

I1. Srief history of II

the dev~lopment of j

Iatomic theory. I

II

II

I2. The laws of: IThe basis fot each

IIof the' laws.

IConservation ofI

I

Mass, Definite II

Proportions, andII

Multiple II

Proportions. II

II

II

J. Contributors to IThe hypotheses of

I

the development ofIeach contributor.

Ithe atomic theory.I

II

I

II

4. Metals and iI

non-metals. II

II

I'f

IS. The relative mass I

Iand charge of I

I

protons, neutronsI

Iand electrons. I

IAtomic number, massl

Inumber,isotopesI

Iand relative atomicl

Imass. I

Ii

II

I6. Simple electronic I

Istructure of atoms I

Ilimited to the I

Ifirst 20 elementsI

Iwith Lewis dot I

Idiagrams _.

o·I

II

I

7. The relationship I

Ibetween the outerI

Ielectronic I

Istructure and theirl

\

groupings into It

families. \

,

TOPIC

ATOMIC STRUCTURE CONT'D

-l6-

I

II

.CORE CONTENT .IEXTENDED CONTENT

II

II

II

I8. The idea that I

Ielectrons are I

Iresponsible forI

Ichemical behaviour. I

II

II

I9. Ele~ents have I

Irelative I

Iat rxactions forI

Ielectrons. I

II

II

IlO.Electronegative, I

Ielectropositive andl

Irelate this to the I

1

elements in a II

Periodic Table. II

II

II

II

II

11.Theformation of IElectronic

I(+) and (-)ions tolconfigurations

Iobt:ain stable Iof(+) and

Ielectronic I(-) ions.

Iconfigurations. I

II

1

I

-]7-

II ':TOPIC

ICORE CONTENTIEXT£NbEb CONTENT

I

III I

3.4 BONDINGII. Bonding as an I

Iattractive, forceI

Ibetween particles.I

II

II

I2. Ionic, covalent IA metallic bond.

Ibond and examplesIMetallic bonding

Iand properties ofIto explain

Isubstances Ielectrical

J

exhibiting thatIconductivity.

Ibonding. "Dative covalent

IIbonding. Predict

IItype of bonding.

II

II

II

II

II

4

'l'HE MOLE CONCEPT I1. Symbols for the II

first 20 elementsI

I

of the periodic II

table, and the I

'"

Isymbol for otherI

~1!

Icommon elements II

--- Bromine, II

Iodine, Copper, II

Lead, Zinc, II

Manganese,Iron,II

Gold, Mercury, II

Silver, Tin. I,

II

II

2. Valency of an I

Ielement '. I

II

II

IJ. Fonnulae of I,

Icompounds using I

Ithe valencyof1

Ithe element). I

I,

I\

I

4. Radicals. I\

I\

I

-19-

I I" TOPIC I CORE CONTIiliT I

1 1

I I4. THE MOLE CONCEPT CONT'O 112. Molar mass of a I

I compound giv~n it~ II formula and'a table II or ~elativeatomic II masses. II II II \113. Law of Conservation II of Mass. I11

I II II I114. Empirical formula II and molecular I1 formula. I

I II I115. Solute, solvent andl

I solution and II solubility of I\ solutes. II II II Problems involving II concentrations of II solutions given II data. (Not II calculating II molarity of II solutions.) II II I1 1

I II II II II I116. Ohe mole of any II.gas occupies the II same volume at II room temperature II and pressure, and II standard tempera- II ture and pressure. I

Calculations uSlng

equations (in termsof mass~s, reactants

and products) andrelate the results

to the Law of

Conservat.ion

of Mass.

Percentagecomposition

of a compound.

given its formula.

Derivations of

Empirical andmolecular formulae

of compounds.

Concentration of a

solution in moles

per cubic decimetreand in grams percubic decimetre.

mol/dm'" and

gjdm:'

and mol dm-3 and9 dm-3

as units of

concentration.

Mass of a solid required

to make up a giv~n volumeof solution knowing thefinal concentration

of the solution.

Balanced chemical

equations involvingvolumes of gases.

--20-

Strength andconcentration of

an acid or base.

Calculations of

molarity, volumeand nwnber of

moles.

Simplestoichiometric

calculations

involvingneutralizationreactions.

[Ir] see below

CORE CONTENTTOPIC

ACIDS, BASES and SALTS5

I ,I EXTRND£D CONTENT

_____________ ,__ ~--_~ I ----1 I

I J

I II II LCharacteristic of, 1

I acids and bases, II . w I12.The meaning of the II terms acid and alkalil

I in terms of the ions I:1 they contain or II produce in aqUeous II solu tion - I1I

IJ.A qualitative' II treatment of the II use of indicators II and the pH scale to II determine acidity, II alkalinity and II neutrality. II I14.Basicity of an Ir acid. II IjS.Neutralization II reaction(titration) II Ila.Metallic and II non-metallic oxides II (ref. oxygen 11.2) Ij I17.Normal salt and II acid salt. II IIS.Preparation of salts. II II I. Preparation of II soluble salts by II the action of II acids with metals II soluble and II insol1lblebases, II and carbo.nates. II II 11. Preparation of II insoluble salts I\ uy precipitation. \

5 . 1 PROPERTIES OF, ACIDS,BASES AND SALTS.

l"](Molarity of acid) X (volume of acid) No. Noles'acid in balanced equation

(Molaritj of base) X(volume ot base) NO.,Moles based in balanced equation

-2l-

EXTENDED CONTENT

Determination of

heat of combustion

and heat of Neut­

ralization energycurves.

Reactions occurringat the Anode and

Cathode.

Demonstrate an

understanding of why

ionic compoundsconduct when fused

or in solution, butnot when solid.

Complete ionelectron equationsat the Anode and

Cathode.

Rationalize changes

in pH of a solutionwith reference tothe formation of

NaOH and the com­

parison between

electrolysis ofCuso .•with inert

or copper electrodes

TOPIC

ENERGY CHANGES IN

CHEMI cAL RE1\CI'IONS

I .1·

I CORE CONTENT I_________ 1. , _

'. I .... IJ.2 IDENTI"FICJ\TION OF IONS I 1. Anions~' 1

I HCOj , CO=-<- II cr, SO~- II 2.. Cations: II Li', Na' .,.- II K', c~=-<"

I Ba"', Pb"', Cu=-<' II NH4.-". re"', Fe:}' II I-1g;'>~, Zn"·.· II . I1 1. Exothermlc and I

I endothermic re- II actions. II II II II 2. Ions, electrolyte, II electrodes and II electrolysis. II II 3. Properties.of II electrolytes. Dia-I

I grams of electroly-I

I ·sis of compounds. II Uses of II ele~trolysi~ - e·g·1

I Electroplating. II II II II 1

I II I11

I II I

·11

I II II II II II II II II II II II I

6. 1 HEAT ENRRGY

6.

6.2 ELECTRICAL

-22--

I

...I

TQPIC

I(ORE CONTENTIEXTENDED' CQNTENT

I

...

II

I7.

SPEED Of REACTION I1. Collision theory IEnergy diagramsI

and experiments Icatalyst.

Ito 'affect. the rate. I

II

II

I2. Haber and Iconsi:!iyation of

IContact processes.Ienergy, Le Chatelier's

IReversible IPrinciple,

Ireactions. Suitable I'Optimum conditions. I

Iccmdi tions, I

Itemperature, IExplanations for

Ipressure (if any)Ithe effects of

Iand cata~ysts. Iconcentration,

IIpressure

IIparticle size~

I3. Equilibrium withIcatalysts and

Irespect to Itemperature

Ireversible Ion rates of chemical

Ireactions. Ireactions ..

II

II

8.

REOOX RE.AcrIONS III

II

1. Oxidation, II

reduction (it I

Iwould be useful if I

Ithe historical I

Iorigin of theseI

Itwo terms could be I

Iexplained) . I

II

I

2."LEO" and "GER" II

electron transferII

as related to II

oxidationandII

reduction. II

II

II

II

J ."Oxidation" of a IHalf-reactions

Imetal showing theIshowing the element

I

transfer of Ithat lost/gained

Ielectrons. Ielectrons.

I

II

IOxidizing/Reducing

I

IAgents.I

-23-

I

ITOPIC

ICORE CONTENTIE.XTIlliDED CONTENTI

II

I'3.

PERIODIC TABLE. \ \

II

9.1 PERIODIC TRENDSI1. The Periodic Tabfe I Comparison andI

as a Iilethodof Iform of oxides andI

classifying Ihalides formed byI

elements. Iperiods 2 and 3.I

II

II

2. The change from. II

metallic to II

non-metallic II

character II

across a Period.II

I9.2 GROUP TRENDS AND

I1. Lithium, sodium ICHARACI'ERISTICS

Iand potassium. II

II

2. Beryllium, II

magnesium, calcium. II

II 3. Carbon( silicon.

j1

III 4. Oxygen, sulphur.

I.. II"'

IS. Fluorine, chlorinelI bromine and iodine, \II Helium, neon andI

Iargon. I

IIGeneral

IIcharacteristics

IIof first

IIseries transition

IIelements.

II.

10.METALS 1 I

II

10.1 PROPERTIES OF METALSI1. Their general I

Ichemical and 1

Iphysical I

Iproperties related I

Ito their uses. \

II

1

2. Reference to iron II

iron alloys, II

aluminium, copperII

zinc (corrosion/II

prevention) . \

--24-

Their displacement

from aqueoussolutions and from

their oxides.

series i.e.

iodine, bromide,

chlorine,fluorine.

Reduction of

their oxides by

hydrogen and bycarbon.

Use of standard

electrode potentials

to predict reactions.

.......TOPIC

(Electrochemical

10.2 REACTIVITY SERIES

I Ii CORE ~oNTfufr I 'EXTENDED C:UNTENT

_________ , 1 "

I '" ' I.I 1. Sodiwm, calciUm, II magnesium, aluminium, I

series)1 zinc, iron, lead, II (hydrogen) and II copp~r.' , "I II Their relative II reactivity II illustrated, where II appropriate, by the II following reactions: II ' II a) Their reactions wi~h I{a)

I oxygen, water and/or II steam and dilute I) hydrochloric acid. II II b) The action of heat l{b) The halogens in

I on their carbonates I the reactivity

I and their nitrates~ II II II I\ II J (c)I II \I II II I (d)I II II II 1. General principles II related to the II reactivity'series. II II 2. The essential II reactions involved II in the industrial II produ2tionof II aluminium (from pure II A1203 (Electrolytic II extraction ,of II aluminium) and iron II (from haematita). II (Extraction by II heat-Blast furnaCe II Schematic diagram fori) industrial processes_ I

10.3 EXTRACTION OF METALS

,~'•

-2'7-

I

ITOPIC

ICORE CONTENTIEXTENDED coNTENTI

II

I11 NON- KETl\LS

II11 . 1 HYDROGEN

1,1. A product of theII

reaction between II

II

a)reactive metalsII

and water and/orII'

steam. II

II

b)metals and acids.II

II

I)

2.Identification, II

properties and uses.II

II

3. Water.Causes ofII

hardness,its effect II

on soaps and II

detergent and itsII

removal.Pollution1

Iof water.An outline I

Iof the purificationI

Iand recycling of I

I

water. I;,j;

\I\

1

11 . 2 OXYGEN

I1.Preparation from II

hydrogen peroxide.I\

Identification, II

properties and uses.II

I1

2.Classification ofIChemical equations

Ioxides as acidic, I of reactions

Ibasic,amphoteric or Iinvolving acidic/

\

neutral. I basic/amphoteric

IIand neutral oxides.

II

I3. Rusting, combustion I

Iand respiration. I

IThe approximate I

\

composition by \

Ivolume of the air:I

Iits variability andI

Icommon pollutants.I

I

Rust prevention: II

painting, 1

\,

galvanizing. \

1

I

-26-

I

ITOPIC

ICORE CONTENTIE:XTENDED CONTENT

II

II

11.) NITROCEN

I1. Uses of nitrogen. INitrogen cycle:

Iref. Haber processI

I5.1.2; I

IUses of ammonia andl

Iqf arrunoniumsalts. I

II

II

I2. The displacement ofl Manufacture, uses

Iammonia from itsIand properties of

Isalts. Initric acid.

IIdentification ofI

IaInrnoniaand itsI

Ireactions with I

I(a)acids I

II

I(b)aqueous I

II

Isolutions of A13', I

ICu''<"'',Fe:..!"',Fe3" I

I2n2'(formulae ofI

Icomplexes are not I

Irequired) . I

I

I

II

II

11.4 SULPHUR

I1. ref Contact processl Extraction of

I5.7.2. Isulphur by the

IIFrasch process.

I\

I2. The reactions of I

Isulphuric acid I

II

Ia)" as an acid,I

II

Ib)as an oxidizingl

Iagent withI

Ispecial I

IreferencetoI

Icopper, I

II

Ic)as a \

IdehydratingI

Ireagent I

Iwith sugar and I

Ihydrated copperl

Icopper (II)I

Isulphate.\

I

I

-27-

I

1

.TOPIC

ICORE. CONTENTIEXTENDED CONTENT

II

II

11 .5 Cffi,ORINE11. Tbe oxidation of I

Ihydrochloric acidI

<.;, •.~

Ito chlorine .• II

Identification ofII

chlor,lne and its1I

reactions with II

metalsBr-(ag) ,II

r(aq) ,and theII

conversion of II

Fe'.,!,.to Fe:~+. II

II

2. Outline manufacture I Equations involvingI

of chlorine by the Ithe electrolyticI

electrolysis ofIprocess.I

brine. II

II

3. The uses of 1

Ichlorine. I

II

II

11.5 CARBONI1) structure of I

Idiamond and I

Igraphite I

c~

Irelated to theirII

properties and II

lJses. I

II

I2) The reducing pro- I

Iperties of carbonI

!

and of carbon II

monoxide. I1

II 3) Carbon monoxide as

II

Cl. product of II

incomplete II

combustion. II

Its poisonous II

nature. II

Ir 4) Carbon dioxide - a

II

product of II

respiration andII

the complete I\

combustion of \

\

carbon compounds.II

Identification ofI\

carbon dioxide and \

its uses.

-2B-

I

tTOPIC

ICORE CONTENTIEXTENDED CONTENT

II

II

CARBON CONT'DI5. Carbonates - their I

Ithermal I

Idecomposition I

Irelated to the I

Ireactivity series.I

IIThe relative

IIsolubilities of the

IIhydrogencarbonate

IIand the carbonate

IIof calcium with

I

, Ireference to hard

I" Iand'soft water.

II

I5. The industrial I

Iimportance I

Iof calcium I

Icarbonate" e.g.I

Iin the productionI

Ilron. I

-:-29-

I

ITOPIC

ICORE CONTENTIEXTENDEI) ·CONTENT

II

II

12. ORGANIC CHEMISTRY

Il.Coal,natur.al gas"1

Iand petroleum asI

I,fuels and how theyI

Icame to be. IFractional ~i~tillation

IIand cracking of crude oil

IIas a source ~f organiG

IIcompounds.

II

I2.The structure andI

Inames of the I

IunbranchedalkanesI

Icontaining up toI

Ifour carbon atoms.\The concept of 1SO-

IImet'l$m,illustrated

IIby C4H.lo'

1

\

I3.The concept of I

Ihomologous series,I

Iincluding generalI

I

characteristics. II

I\

4. Alkanes. ICombustion - incompleteI

Substitution Iand complete.]

reaction with I\

bromine. 1

II

I5.structure of I Addition reactions

Ialkenes:etheneIof Br2' C12 for

Iand propene only.Ialkenes.

IThe formationofI

Ip6ly(ethene) as an \

Iexample of additionl

Ipolymerization ofICondensation of

Imonomerunits.Ipolymers. e.g. nylon

II

II

I 6. Alcoh61s,typif led ICarbohydrates -

Iby ethanoL itsIsugars -glucose,

Iformation by Ifructose.

\

fermentation, II

its uses and II

its oxidation II

to ethanoic acld.~II

IStructure of

\

Iethanoic acid/\

\esterification/reaction

IIwith ethanol.

\

I

-="\0-

Reasons for and

against nuclear

energy as analternative source.

TOPIC

13. SOCIAL"ECON()HIC.ENVIRONMENTAL AND

TECHNOLOGICAL

APPLtcATIONS OF

CHEMISTRY

I II CORE. CONTENT I .~ED CONTENT

_____ -- __ 1 1 _

I II II II II II II II 1.Tne sea as a sourcel

I of magnesium, II bromine and common II salt. Rocks as a II .source bfbauxi te, II haem~ti~e and rock II 3alt a~d 6ther Ilares. II II 2. Finite nature 6f II supplies of fossil II fuels, gas, oil, II coal,aragonlte and II minerals. II Alteinative sources II of energy; ~.g. II solar, nuclear. II II II 3. The chemical and II economic ·importancelI of conserving and II recycling materialsl

I such as iron and II aluminium. II II II I.

13·.1 MINERAL AND RNERGYSOURCES

-31-

I

ITOPIC

ICORE CONTENTIEXTENDED CONTENT

II

II

13 .2 POLLUTION

I1. Air·pollution. IEffects -of ac:;idI

The h~rmful effectIgases, and acid

Iof sulphur dioxide Irain from sulphur

Ion metals,stone~otkldioxide and

Iand living things.Initrogen dioxide.

IThe poisonous I

Inature of carbonI

Imonoxide, nitrogen I

Ioxides andleadI

Icompounds. The I

Inon~biodegradableI

Inature of many I

Iplastics. I

II

I2. The reduction of I

Ipollution e.g. I

Ismokeless' zones,I

Ilead-free petrol.I

IDangers of I

Iasbestos, II destruction of I

Iozone layer, I

Ipreventative I

.~

Imeasures. II

II

3. Harmful effects of II

untreated sewage,II

chemical waste, II

fertilizers, pest-II

icides and deter -II

gents. II

I1

I13.3 FOOD SUPPLY

I1. The need for IThe manufacture of

Ifertilizers. Initrogenous

IThe importance ofI .. fertilizers.

IN, P and K to plantlExplanation .of

Ilife. Iwhat ,happens to

IIN, P and K fertilizers

IIin soil.

IIReasons for and

IIagainst fertilizers.

II

I2. The need for food I

Ipreservatlvessuch I

Ias salt, sulphurI

Idioxide and I

Iethanoic acid. I

II

-32-

Reasons ~or andagainst pesticides.

TOPICI II ;...CORE CQNTENT . I .EXTENDED.CONTENT

I ~ I ~ __ ---------~I II 1. The u~eof II chemical~ in the Ij ~revention and II treatment·of II illness. II The potentially j

I harmful effect of II some chemicals, II e.g. alcohol, II pesticides and II fertilizers, J

I narcotics II controlled II substances. II II TelTIs:medi~ine, II drug~ antacid, II analgesic. j

I I

·13.4 USE AND ABUSE· OF..

CHEMICALS

El

-33-

This section describes the various ~ethods us~d in thetesting of theasse~sment objectives for BGC$E, Chemistry.

<,~l

6 _:t OBJECTIVE QUESTIONS (PAPER 1)

Objective questions (Multiple, Choice ) will, ,oe of '__nefour-option type and wlllail be' compulsory. Objectivequestions testa ~id~~biiity iangeand~chie~e a widecoverage of the syllabus.

6_2 SHORT ANSWER QORSTIONS (PAl?ER 2)

A short~answer question is one to which the answer can begiven in a single word, a well constructed sentence, adiagram and/or a short calculation.

Short-answer questions test ft wide ability range andachieve a wide coverage of the syllabus. '

6 _:3 S"I'&UC-XUl<EDQUE..STIONS {l?APER, 2 ANDl?APER :3}

Each structured questiqn may be illustrated by drawings,diagrams, data etc. Clear guidance will be given as tothe pattern of response required in each part of thequestion.

The structuring of the questions may be linear, with eachitem (or part) depending on the previous one, or,branched, with each item (or part) depending on a commonstem and independent of other items.

structured questions have an incline of difficulty andtest a wide ability range.

6_4 FREE-RESPONSE QUESTIONS (PAPER 2iFree-response questions (short' paragraph completion type)will comprise one section of the optional paper.

Free-response questions require the candidate to explain,discuss or perform a calculation on material for which theexaminer has 'not provided ,a pattern of response.' Thecandidate is expected to demonstrate communication,planning and organizational skills. These questions willbe designed to test the upper end of the ability range.

-34-

Oral qU"E~stions.may.be used in conjunction with theintetnalassessmentof practical skills (e.g. by theexternal mooerator) .....

This will comprise practical as well as written.assignments; and may involve any combination of objective,short-answer, structur~d and· free-response questions.

Detailsforas~essing couisework is given in th~ section"Inte-rnal··Assessment of Practical SRills. 11

6 _7 ALTERNATIVE TO INTERRAL ·ASsES.SME:RT .. .. . - .. -' -'

OF .PRAC'TICALWORX{ COMP<:ll!iIEllI"r 4}

External candidates will be eipectedto write anexamination to test their ·practical skills. This paperwill hot exceed 2 h6urs in length.

Internal candidates experiencing extenuating circumstancesmay with the approval of the Examination Board be allowedto write this examination.

-3t)-

" " "" "

The information which follows is provided to assist teachersin making valid and reliable assessment of the experimentalskills specified in the assessment objectives of theexamination.Attention is drawn to the 'Handbook on Internal Assessment ofPractical Work'.

The experimental skills A to D to be assessed are given below:

A. Using and organising techniques, apparatus and materials.

B. Observing, measuring and recording,

c. Handling experimental observations and data.

D. Planning; carrying out and evaluating investigations.

The four skills carry equal weighting.

l\ll assessments must be based upon experimental work carriedout by the candidates.

It is expected that the teaching and asseSsment ofexperimental skills will take place throughout the course,but that the actual assessment which will contribute to theexamination grade should be conducted during the second andthird year of~he course.

The assessment scores finally recorded for each skill on theAssessment Sheet (Appendix A) must represent the candidate'sbest two marks for each skill. "

For candidates who miss the assessment of a given skillthrough "no fault of their own, for example because of illness,or through lack of facilities and who cannot be assessed onanother occasion, Ministry of Education procedures for specialconsideration should be followed as specified in the currentHandbook for Centres. However, candidates who for no goodreason are absent from an assessment of a given skill, shouldbe given a mark of 0 on that occasion.

Teachers must ensure that they can make available to themoderator the evidence for the two assessments of each skillfor each candidate.For skills A to D, inclusive, information about the tasks setand how the marks were awarded will be required. For skillsBr C and D, the candidate's written work will also berequired.

-36-

EXPE.RIMENTAL SKTT.T ~ ANn ASS~ENT OBJEC'TIVF..S

Experimental Skills

A Using and organising techniques,apparatus and materials.

B Obs~rvingj measuring andrecording.

C Handling experimentalobservations and data.

D Planning, carrying out andevaluating investigations.

Assessment Obj~ctives

(3.3~ 3.17, 3.20)

(3.4,3.18, 3.19)

(3.7, 3.9, 3.16)

(3.10~ 3~15, 3.21)

7_1 Criteria for Internal Asses~ritof PraGtica·l Skills:

Each skill must be as~essed on a six (6) point scale,level 6 being the highest level of achievement.

Each of the skills is defined in .terms uf three levelsof achievement at scores of 2, 4, or 6.

A score of 0 is available if there is no evidenceof positive achievement for a skill.

For candidates who do not meet the criteria for a scoreof2, a score of 1 is available if there is some evidenceof positive achievement.

A score of 3 is available for candidates who go beyond thelevel dcifined for 2, but who do not meet fully thecri te r i a for 4.·

Similarly, a score of 5 is available for those who gobeyond the level defined for 4, but do not meet fully thecriteria for 6.

-37 -

Skill A - USING AND ORGANIZING TECHNIQUES, APPARATUS ANDMAt'ERIALS .

Score

1 7;

2 - Follows written, diagrammatic or oral instructions toperform a single practical operation.

Uses familiar apparatus and materials adequately, needingreminders on points of safety.

3 7;

4 - Follows written, diagrammatic or oral instructions toperform an experiment involving a series of step-by-steppractical operations~

Uses familiar apparatus, materials and techniquesadequately and safely.

5 *

6 - Follows written, diagrammatic or oral instructions toperform anexperim~nt involving a series of practicaloperations where there may be a need to modify or adjust

r one 'step in the light of the effect of a previous step.~

Uses familiar apparatus, materials and techniques safely,correctly and methodically.

* See the explanation under 7.1, Criteria for InternalAssessment of Practical Skills.

SKILL B

Score

1*

-38-

.. , ..OBSERVING, r-1EASURING ANIj, RECORDING

2 ,..-.Makes observations or readings given d~·'.':ailedinstructions ....

Records results in an appropriate manner glven adetailed format.

3*

4 - Make relevant observations or measurements havingbeen given an outlinefoimat or brief guidelines.

Records results in an ~pptopriat~manner given anoutline format.

5*

6 - Makes relevant observations or measurem~nts to adegre~ bf accuracy appropriate to theinstruments or techniques 'used.

Records results in an appropriate manner given noformat.

*See the explanation under 7.1, criteria forInternal Assessment of Practical Skill~.

- 39 -

Skill C - lUUfDLING EXPERIMENTAL OBSERVATIONS AND DATA.

Score

1 I(

2 - Pioces~es results ~n an Bppropriate manner glven adetailed format ....

Draws an obvious qualitative conclusion from the resultsof an experi~ent;

3 *

4 - Processes results in an appropriate manner glven anoutline format.

Recognizes and comments on anomalous results.

Draws qualitative c6nclusions which are consistent withobtained results and deduces patterns in data.

5 *

6 - Processes results in an appropriate manner given no format

Deals appropriately with anomalous or inconsistent results

Recognizes and comments .on possible sources ofexperimental error ..

Expresses conclusions as generalizations or patternswhere appropriate ..

* See the explanation under 7.1. criteria for InternalAssessment of Practical Skills.

--40-

Skill D- PLliliNING, CARRYING OUTNID EVALUATING INVESTIGATIONS

Score

1

2 - Suggests and carries out a simple experimental strategyto investigate a given practical problem:

Attempts 'trial and error' modification in the light ofthe experimental work carried out.

3 *

4 - Specifies and carries out a sequence of activities toinvestigate a given practical problem.

In a situation where there. are two variables, recognizesthe need to keep one·of them constant while the otheris being changed.

Comments critically on the original plan, and implementsappropriate changes in the light of the experimental

* work carried out.

5 *

6 - Analyses a practical problem systematically, produces alogical plan and carries out the investigation.

In a given situation recognizes that there are a number.of variables and attempts to cohtrol them.

Evaluates chosen procedures, suggests/implementsmodifications where appropriate and shows a systematic.approach in dealing with unexpected results.

* See the explanation under 7.1, Criteria for InternalAssessment of Practical Skills.

-41.-

Areas which might be suitable for Assessment

The following is a ~irtiallist of suggested practical exerClsesthat can be used to assess exp~rimenta~ skills A -D.It must be strongly stressed that the following examples do notform a prescribed list of exercises but are provided only asillustrative material ..

(a) Rate of decomposition of dilute hydrogenperoxide/rnahganese(IV) oxide. Effect of time,. temperatureand concentration.

Ib) Determination of the formula of salt hydrates, e.g.magnesium sulphate.

lc) Precipitation of hydroxides using aqueous ammonia orsodium hydroxide solution.

Id) Rate of reaction between calcium carbonate and diluteacid.

(e) Separation of mixtures including solid/solid and~ liquid/liquid.,

(f) Preparation of crystals of a soluble salt.

(g) Investigation of reacting masses, e.g. reduction ofcopper(II) oxide.

(h) Investigation of electroplating.

(i) Simple cation/anion analysis.

(j) Investigation of the. reaction between ammonium compoundsand bases.

(k) Investigation of the reaction between solid carbonatesand dilute acids to produce carbon dioxide.

-42-

(1) Rate of pto ducti on of hydrogen ftom·clLl.uteac.id andmagnesium using a gas syringe ... .

(m) Investigation of thehardness'v'of various tyPes of water.

(n) Investigation·· of redox .reactions , e.g ...iron! 11) compoundstoiron(III) compounds with. various oxidizing agents.

(0) Investigation of the order 6£ reactivity of metals.

(p) Investigation of the decomposition of metal nitrates andmetal carbonates.

-43-

-1 - 2 NOTES FOR GUIDANCE ON I.N'TERNAL ASSESSftKR'.I."OF PRAC"':l'ICAL'. WORK

(see.··Jt~~ .On·.IDt.e.rnal·~tof .J?ract.:i.ca.l Work for IDO~ deta.:L1)

The following notes are intended to provide teachers withinformation to help .them make valid and reliable ass·.:smentsof the skills of their candidates.

The assessments should be based on the principle of positiveachievement~ Candidates should be given opportunities todemonstrate what they understand and can do.

It is exp~cted that candidates will have had opportunitiesto acquire a given skill before assessment takes place,but each assessed experiment itself must be new tothe students.

It is not expected that all of the practical work undertakenby a candidate will be assessed.

Assessments can be carried out at any time during the course,but the actual marks which will contribute to the examinationgrade should be obtained from assessment during the secondand third year of the course.However, at whatever stage assessments are done, thestandards applied must be those expected at the end

\ of the course as exemplified in the criteria for the skills.

Assessments should normally be made by the person responsiblefor teaching the candidates.

It is recognized that a given practical task is unlikely toprovide opportunities for all aspects of the criteriaat a given level for a particular skill to be satisfied. Forexample, there may not be any anomalous results (Skill C).However, by using a range of practical work, teachersshould ehsure that opportunities are provided for all aspectsof the criteria to be satisfied during the ,course.

The educational value of extended experimental investigationsis widely recognized. Where such investigations are usedassessment purposes, teachers should make sure thatcandidates have ample opportunity for displaying the skillsrequired by the Scheme of Assessment.

It is not necessary for .all candidates in a centre, or 1n ateaching group within a centre, to be assessed on exactlythe same practical work, although teachers may well wish tomake use of work that is undertaken by all oftheir candidates.

-44-

........

When an assessment is carried out oh group work, the teachermust, ensure that ,the individual contribl.1tionof each,candidate ~an be assessed.

Skill A may not gerierat~ a written product from thecandidates. It will often be',asset;!sedby watching thecandidates ~arrying out.pract~cal w6tk. '

,SkillsB, C and D will us~ally generate a written ~roductfrom the candidates. This product will pro~ide evidericefor moderation.

Raw scores for individual practical assessment$ may be glvento candidates as part of the riormalfeedback from thete~cher. The final; internally moderated, total score,which is submitted to the Ministry of Education, shouldnot be given to the candidate.

-45-

7_3 HODF,.RATION

(a) :I:N'TER.NAI.. 'MODERATION

When sever~l teachers in a centre are involved in internalassessment, arrangements must be made within the centr~ forall candidates to be assessed to a common standard.

It is ~ssential that within each Centre the marks for eachskill assigned within different teaching groups(e.g., different classes) are moderated internally for thewhole centre entry. The centre assessments will then besubject to external moderation.

(b) E.XT:ERNAL MODKRA~rION

Assessment sheets (see Appendix A) are to be submitted tothe Ministry of Education no later than the specified date Inthe year of the examination. For external moderation theMinistry of Education will require, for a specified sample,evidence which must include for skills A toD inclusive,information about the tasks set and how the markswere awarded. In addition, for skills B,C, andb a specifiedsample of candidates' written work will be required. A furthersample may be required. All records and supporting written workshould be retained until after .the publication of results.

Centres may find it convenient to use loose-leaf A4 filepaper for assessed written work. This is because exampleswill be sent through the post for moderation and postagebills are likely to be large if whole exercise booksare sent.

The samples sent to the moderator should haVe the sheetsstapled together in th~ top left hand corner and should beclearly labelled with the centre number and the candidate'sname and number. On each piece of work the skill(s) assessedand the mark awarded to each skill must be stated.Authenticated photocopies of the sample required would beacceptable.

-46-

Add, subtract, multiply and divide"

Understand an(t,use decimals, fractions, averages;percen tages, .ratics •..

Recoghizeand use expressions in d~cimal and scientificnotation.

Recogniz~ the variability and unieliability lnexperimental·measurem~nts.

Make approximations and estimates.

Undertake mensuration of a triangle, rectangle, cuboid andcylinder;

substitute numbers for letters in simple equations.·

Solve simple equations.

Interpret graphs and charts.

Use positive whole number indices.

Make approximate evaluations of numerical expressions.

Use direct proportions.

ADDITIONAL KATlIEMATICAL SKTT.T~c; REQUIRED FORSTUDENTS A"I"'T'EP'IP'T GRADES A -B

Manipulate simple equations and find their solutions.

Select appropriate axes and scales tor graph plotting.

Choose by inspection the best straight line or curve thatwill fit through a set of points on a graph.

Determine the gradient (slope) and intercept of a lineargraph.

Use inverse proportions.

Use negative whole number indices.

--47-

9 _ GLOSS.nR~ 01:"T£RHS USED IN SCIENCE. P.1'>PERS

It is hoped that the glossary will prove helpful tocandidates as a guide,i.~~ it is neither exhaustive nordefinitive. The glossary has been deliberately kept brier notonly with respect to the number of terms included but also tothe descriptions of their meanings. Candidates shouldappreciate that the meaning of a term must 'depend, in part,on its context.

1. DEFINE {the term(s) ...} is intended literally, onlya formal statement or equivalent paraphrase beingrequired;

2. WHAT '00 YOU UNDERSTAND BY/Hhat is meant by {theterm(sJ ..•}normally implies that a definitionshould be give~, together with some relevantcomment on the significance or 'context or theterm(s) concerned, e~pecially where two or moreterms are included in the question. The amount ofsupplementary comment ifitEindedshould he'interpreted in the light of the indicated markvalue.

")

.J • STATE implies a concise answer with little or nosupporting argument, e.g. a numerical answer thatcay\ readily be obtained "by inspection'.

4. LIST requires a nUIT~er of points, generally each ofone word, with no elaboration. Where a given .number of points is specified this should not be'exceeded.

S. EXPLAIN may imply reasoning at some reference totheory, depending on the context.

6. DESCRIBE reguire~ th~ candidate to state in words(using diagrams where appropriate) the main pointsof the topic. It is often used with referenceeither to particular phenomena or to particularexperiments. In the former instance, the term.usually implies that the an~wer should includereference to (visual) observations associated withthe phenomena.

-48-

In other contexts, DESCRIBE and GIVE AN ACcouNT OFshould be interpreted more generally , i ~e .:t.h~:candidate h~s greater discretion about. the n~tureand the organiiation of the material to be includedin the answer~ DESCRIBE.andEXPLAIN may becoupled, as may STl\TE and EXPLAIN.

7. DISCUSS requires the candidate to give a criticalaccount of the points involved in the topic.

8. OUTLINE implies brevity, i.e. restricting theanswer to giving essentials~

9. PREDICT or DEDUCE implies that the candidate is notexpected to produce the required answer by recallbut:by making a logical connection between otherpieces of information. Such information may bewholly given in the question or may depend on

answers extracted in an early part of the question.

These terms imply a concise answer with ~osupporting statement required.

10. SUGGEST is used in two main contexts, (i.e. eitherto imply that there is no unique answer (e.g. inChemistry, two or more substances may satisfy thegiven conditions describing an 'unknown'), or toimply that candidates ·are expected to apply theirgeneral knowledge to a 'novel' situation, one thatmaybe formally 'not in the syllabus'.

11. FIND ·is a general term that may variously beinterpreted as CALCULATE, MEASURE, DETERMINE, etc.

12. CALCULATE is used when a numerical answer isrequired. In general, working should b~ shown,especially where two or more steps are involved.

13. MEASURE implies that the quantity concerned can bedirectly obtained from a suitable measuringinstrument e.g. length, using a rule, or mass,using a balance.

14. DETERMINE often implies that the quantity concernedcannot be measured directly but is obtained bycalculation, substituting measured or known valuesof other quantities into a standard formula, e.g.volume, the formula of an ionic compound.

y.,

-49-

15. ESTIMATE implies a reasoned order of magnitudestatement or calculation of the quantity concernedmaking such simplifying assumptions as may benecessary about points of principle and about thevalues.,of quantities not otherwise included in thequestion.

16. SKlh'CH when. applied to graph work, implies' that theshape and/or po~itionof the curve ~eed only bequalitatively correct, BUT candid~tes ~hould beaware that, depending on the context, somequantitative aspects may be looked for, e.g.pa~sing through th~origin, having an intercept .

. -

In 4iagrams,· SKETCH implies .that a simple, freehand-drawing is acceptable: nevertheless, care shoUldbe taken over proportions and the clear expositionof important details. -

-50-

10. GRADE DESCRIPTTONS

" ,", '

The following "grade,descriptions are intended to,give. a generalindication bf the standards likely to have been achieved ,bycandidate~ aw~rded'Gra4~s C and F. Inpr~ctice, the:qtad~

awarded w~llqepend upon the extent to which the candidate hasmet the 'objectives overall, and this might conceal weakness insome aspect of <theexarrii.nationwhich is balanced b~rsuperiorperformance in~6~e other. '

Assessment Objective

3.1, 3.3, 3.4Facts, vocabulary

;~ conventions," physical quantities

and units in whichthey are measuredrequirements forsafety,

1I

I A typical candidate, II for the Award of' a ' II mihimum Grade F II might know ai1dhave II been able to demon- II strate knowledge andlI understanding of howlI to: I'I I1 1

I II II (a) State the II conditions II for r.t.p. and II s.t.p. II II (b) use of the II word 'equation' II.,. II (c) use a spatula II for handling, II solid chemicals. II II (d) State the fact II, that the mass oflI an element is II measured in 'II grams. I

A typical candi­date for'the Awardcfa minimum Grade

'Cmight-know andhave been able todemonstrate know­ledge and under­standing of howto:

State the fact thatliquid and solidmetals conductelectricity.

use the term'molarity'

heat liquids'liquids in testtube safely.

State the unit ofconcentrationmol dm-3

-51-

interpretand analyze datagiven a pie chart.

write simplebalanced chemicalequations.

describethe manufactureof ammonia usingthe Haber process.

define the mole

stating how manyparticles arefound in one moleof substance.

use followingequation to solvesolve for dilutionM~V~ = M2V2with appropriateunits.

apply the theory ofkinetic energy tothe movement ofmolecules insolids, liquidsand gases.

3.1Definitions andlaws.

3.1Informationpresented,invarious forms.

3.13The uses, applica­tions implicationsof physical factsand principles.

Assessment Objective

3.8Use given formulae.

3.12

Apply laws andprinciples.

11

I A typical candidate I A typical candi.,..___ ~ I for the Award of a I date for the Award

I minimwnGradeF I of a minirnumGradeI might know, and have I C might know andI been abl~ todembn~ I have· been able toI . strate knowl,edge and I ...demonstrate. know­I understanding of howl ledge and under-1 to: I standing of howI I to:

_________ 1 1

I II II (a) define element II and compound. II II II I

--------,-- 1

I II (a) use.a simple II straight line II . graph. II I

---------,-- 1

I II (a) wr ite "word' II equations. II II II (b) State that therelI are chemicals II with ~armful II effects related II to air I1 pollution. 1

________ 1 1

I II(a) convert temper- II ature from the II Celsius scale II to the Kelvin .\I Scale .. 1

I I_________ 1 1

I II 1

I (a) solve simple 1

I problems given II Avogadro's Gas II Laws. 1

I II I

-52-

explain diffusionand how it relatesto temperatureand energy of theparticles.

draw simpleenergy leveldiagrams forendothermic andexothermic.

Select apparatusto collect gasover water or ina gas syringe.

explain thediffusion ofsolids, liguidsand gases.

describeendothermicexothermicreactions.

Determine byexperimentationthe most effec­tive method. formeasuring smalland largequantities ofliquid.

IA typical candidate I, AtyPicalcahdi~for the Award of a I date for the Awardrriiniimim"Grade' F I of a minimum Grademight knOw and have I C might know andbeeri"a.bleto demon- I have been able tostrate knowl~dgeandr demonstrate know­uriderStandirigof howl ledge and under-to:. - I standing of how

I to:I~ --IIIIIIIII

and )IIIIIII

Separate a suit-lable mixture by Ifilteration. I

III Perform experl-I ment and drawI graphs showingI rate of decom­I position ofI dilute hydrogenI peroxide/I manganese(IV)I" oxide against"I time, temperatureI or concentration.I ll,nalysisofI results necessary.

IIIIIIr

IIIIIII (a)IIIIII (b)IIIIIIIII (a)IIIII (b)IIIIIIIIIIII

3.6Explain phenomenain terms theoriesand models.

Assessment Objective

3.15Solve problems bydesigning, conductingand interpreting theresults of simpleexperiments.

-53-

A typical candi­date for the Awardota minimum Grade

C might know andhave been able todemonstrateknowledge andunderstanding ofhow to:

Offer reasons fordiscrepancybetween·expectedand actual resultswhen pH of wateris measured.

Establish, givenexperimental data,evidence of arelationshipbetween Variablesand draw anappropriategeneralizationfrom the relation­ship.

3.19

Recognize mistakes,misconceptionsunreliable data,and assurnp~ions.

3.10Draw conclusions andformulategeneralizations.

Assessment Objective I A typical candidate____________ 1 fo~ the Award of a

I minimum Grade FI might know and haveI been able to demon-II strate knowl~dge and)I understandirig of howlI to: II I

-- 1 1 --

I II II(a) Identify a II doubtful point It on a straight II line graph. II II II I1 1 _

--------, II 1

I Select given .II experimental II data and a II series of II possible con- II cLusions or II generalizations, I1 a likely con- I

\ clusion and II support the II choice with II simple reasons II (e. g. 1*l.cation/ anion. I Use of periodicI analysis) . I or groupI I properties.

,",~.-'t.~:.

APPENDTX A

MINISTRY OF EDUCATION

BAHAMAS GENERAL CERTIFICATE OF SECONDARY EDUCATION

INTERNAL ASSESSMENT OF EXPERIMENTAL SKILLS

Subject Name

Centre Name-

,-

Subject No.

Centre No. ------.,---------

1 , I I Internally Moderated Mark for each Skill 1 Total I. Cornments.·( if neces·sary)I Candidate Nmne I Candidate No. 1 Skill A Sk.ill B Sk.ill C Skill 0 I Mark I

\ I ·1 (6) (6) (G) (5) (6) (6) (5) (6) 1 I

1 1 1 1 __ 1 _

\ 1 . \ __ 1_11_1_1_1_1_1 __ 1 __ 1 _

1 1 1__ 1_·_1_1_1_1_1_1 __ 1.. 1 _1. 1 1__ 1_1_1_1_1_1_1 __ 1__ 1 .1 1 1__ 1_1_1_1_1_. _1_1 __ 1__ 1 _\ \ 1_·····_1_1_1_1_1_1_1 __ 1__ 1 _1 1 1__ 1_1_1_1_1_1_1 __ 1__ 1 - _1 1 1__ 1_1_1_1_1_1_1 __ 1__ 11 1 1 I I I I I I 1__ 1__ 1---------\========-=-=--=--=--=1 1==1==1 ==\ ==\==1==1==1_~1 __ 1---------I 1 1 1 I I I I I 1__ 1__ 1---------\-.------\ 1==1==1==\-1==1==1-1 __ 1~_1--------\ 1 1__ 1_1_1_1_1_1_1 __ 1__ 1:·================\ 1 1__ 1_1_1_1_1_1_1 .. 1__ 1 _1 1 1__ 1_1_1_1_1_1_1 __ 1__ 1 -- _

tVI.l:'­I

Total number of Candidates on this. sheet

Total number of Candidates entered by the Centre

Narneof Internal Moderator (BLOCKCAPITALS PLEASE)

Sheet of Signature of Internal Moderator ---------

j)".:' ;;!'IEET~'",t!~',

Tbe Peric,.cU...C Tab.le 0 e· Lbe El~_r::n:.s

83Si

20a.9804

6

C12.011

14

Si28.0855t

32

Ge72591

50

Sn118.710:'

82

Pb20i.2

5

810.811c.

13AI

2U8154

31

Ga69.723c.

49

In114.82

81

- TI.204.383

NOBLEIIIB IVB VB VIB VIIS GASES

f 1\ \ t ~~"~"!\! \! \HHe I\ " ";\ 1 ,00794Q. 4002502·:

7 8 910

N O' F Ne14.0067 .15.9994.t .18.9984.03 20.179

15 16 . 17 18P S Cl Ar

30.97376 32.066"- 35.453· 39.945 i

33 34 35 36As Se .Br Kr

74.9216 78.961 79.904 83.80

[[1 52 53~ 5'Sb Te I Xe

121.75' 127.601 ,126.9045 131,291.~

84' 85 86

Po . At Rn(209) (210) (222)

30

Zn65.39'

48 .

Cd112.41

80

Hg200591

76

Os190.2

'VillA

1\! \! \

/ \/ \

/' \./\/.26 I 27 28 \ 29Fe Co Ni I Cu55.847t I 58.9332 58.69 63.545t

44 45 I 46 .1 47Ru Rh Pd Ag101.07" 102.90551 10642 11078682~

~I, 78 79

Ir I' Pt Au192.221 195 oat 195.9655

25

Mn54 9380

43

Te~75

Re185207

24

Cr51.9S51c.

I\.'A VA

i\ ~i '.

f \

'\

4

Be .901218 ;

12 .!

Mg il

24.305 I .

20 . 21 22 23

Ca Se Ti V40078° 44.95591 47.88' 50.9415

38 I 39 40 41 "I

Sr ,y Zr Nb,8752 I 889059 91224" 92.9064 I

56 ·1 57 72 '1' 73. Ba ,**La Hf Tam,JJ i 138.9055T 178.491 118094791183851

88 89 . 104 105 \, 06

Ra TAe Unq§ Unp§ 'Iunh§i 226.0254 i2270278 (261) (262) (263)

I 11Na122.98977

I 19I K, 39.0983

'-3"7I Rb18546781

55

Cs132.9054

87

Fr(223)

lA IIA IIlA

/A", f\. 1 i, I

H I

1 00794 Cl /

3

Li6.941'

''''_UlI''aJ1I()~~

58 59 60

Ce Pr Nd140.12 140.9077 144.241

61

Pm1145 )

62

Srn150 361

63

Eu151.96

64 65 66 67 68 69 70 \ 71Gd TbDy Ho Er Tm' Yb ,'..Lu157.251 158.9254 162.50t 1649304 ;67.26T 158.9342 173.04' 1174%7

T ";'Cllt'\'Clt1

90 91. 92 I 93 94Th Pa U Np Pu1232 C181 221,0359 2J.:i (J2P.q !J70 7. (2~41

95 I 96 97Am Cm Bk(2:l3) '247) (2~7j

98

et(251 )

99 [100;;\ ' ~~

102No25°

103

Lr1C1!l)

Thevolurne of one mole of any gasLs 21 dm3 (l.itres) at room temperature and pres~ure (r.Lp.)

RECOMMENDED TEXTBOOKS .

. .. - .... '.,-'

1. A New First Chemistry -RamsdenStanley Thomas publishers Ltd.1985

2 . Review Chemistry Amsco

AND AT LEAST ONE OF THE FOLLOWING

3. Nuffield Co~ordinatedSciences - themistryAndrew HuntLongman Group - UK 1988

4. Thinking Chemistry - Lewis and WallenOxfDrd

s. GCSE Chemistry John Murray

ro. Chemistry by Concept - Antony Spiers,"Derek StebbensHeinemann Educational Books1974