chemistry 2005 for teachers

7/28/2019 CHEMISTRY 2005 for Teachers

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CHEMISTRY5070

GCE Ordinary Level/School

Certificate2005


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Nomenclature

The proposals in Signs, Symbols andSystematics (The Association for ScienceEducation Companion to 5-16 Science,1995) will generally be adopted.

Reference should be made to the jointstatement on chemical nomenclature issued

by the GCE boards. In particular, the

traditional names sulfate, sulfite, nitrate,nitrite, sulfurous and nitrous acids will beused in question papers.


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Nomenclature (continued)

It is intended that, in order to avoid

difficulties arising out of the use of l as

the symbol for litre, use of dm3 in place

of l or litre will be made.


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Nomenclature (continued)

In chemistry, fullstructuralformulae

(displayed formulae) in answers should

show in detail both the relative placing

of atoms and the number of bondsbetween atoms. HenceCONH2 and

CO2H are not satisfactory as full

structural formulae, although either ofthe usual symbols for the benzene ring is

acceptable.


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Units, significant figures

Candidates should be aware that misuse

of units and/or significant figures, i.e.

failure to quote units where necessary,the inclusion of units in quantities

defined as ratios or quoting answers to

an inappropriate number of significantfigures, is liable to be penalised.


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INTRODUCTION

This syllabus is designed to place less

emphasis on factual material and greater

emphasis on the understanding and application

ofscientific concepts andprinciples. This

approach has been adopted in recognition of

the need for students to develop skills that will

be of long-term value in an increasingly

technological world rather than focusing onlarge quantities of factual material that may

have only short-term relevance.


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AIMS

These are not listed in order of priority. The aims are to

1. provide, through well designed studies

of experimental and practicalchemistry, a worthwhile educationalexperience for all students, whether ornot they go on to study science beyond

this level and, in particular, to enablethem to acquire sufficientunderstanding and knowledge to


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AIMS (continued)

1.1 become confident citizens in a

technological world, able to

take or develop an informedinterest in matters of scientific

import;


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AIMS (continued)

1.2 recognise the usefulness, and

limitations, of scientific methodand to appreciate its

applicability in other disciplines

and in everyday life;

1.3 be suitably prepared for studies

beyond O/SC level in puresciences, in applied sciences or

in science-dependent vocational

courses.


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AIMS (continued)

2. develop abilities and skills that2.1 are relevant to the study and

practice of science;

2.2 are useful in everyday life;

2.3 encourage efficient and safe

practice;2.4 encourage effective

communication.


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AIMS (continued)

3. develop attitudes relevant to sciencesuch as

3.1 concern for accuracy and

precision;3.2 objectivity;

3.3 integrity;

3.4 enquiry;3.5 initiative;

3.6 inventiveness.


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AIMS (continued)

4. stimulate interest in and care for the localand global environment.

5. promote an awareness that

5.1 the study and practice of science are

co-operative and cumulative activities,and are subject to social, economic,technological, ethical and culturalinfluences and limitations;

5.2 the applications of sciences may beboth beneficial and detrimental to theindividual, the community and theenvironment.


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ASSESSMENT OBJECTIVES

A. Knowledge with understandingStudents should be able to demonstrateknowledge and understanding in relation

to:1. scientific phenomena, facts, laws,

definitions, concepts, theories;

2. scientific vocabulary, terminology,conventions (including symbols,quantities and units);


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ASSESSMENT OBJECTIVES (continued)

3. scientific instruments andapparatus, including techniques ofoperation and aspects of safety;

4. scientific quantities and theirdetermination;

5. scientific and technologicalapplications with their social,economic and environmentalimplications.


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The subject content defines the factual

knowledge that candidates may be

required to recall and explain. Questionstesting those objectives will often begin

with one of the following words: define,

state, describe, explain or outline.


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B. Handling information and solvingproblems

Students should be able - in words or

by using symbolic, graphical and

numerical forms of presentation - to:

1. locate, select, organise and presentinformation from a variety of

sources;


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2. translate information from one formto another;

3. manipulate numerical and other

data;4. use information to identify patterns,

report trends and draw inferences;

5. present reasoned explanations forphenomena, patterns andrelationships;



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6. make predictions and propose

hypotheses;

7. solve problems.


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These assessment objectives cannot beprecisely specified in the subject contentbecause questions testing such skills may

be based on information that is unfamiliarto the candidate. In answering suchquestions, candidates are required to use

principles and concepts that are within thesyllabus and apply them in a logical,reasoned or deductive manner to a novelsituation.


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Questions testing these objectives will

often begin with one of the following

words:predict, suggest, construct,calculate or determine.


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C. Experimental skills and investigations

Students should be able to:

1. follow a sequence of instructions;2. use techniques, apparatus and

materials;

3. make and record observations,

measurements and estimates;


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4. interpret, evaluate and report upon

observations and experimental

results;5. design/plan an investigation, select

techniques, apparatus and materials;

6. evaluate methods and suggestpossible improvements.


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SCHEME OF ASSESSMENT

Candidates are required to enter forPapers 1, 2 and either Paper 3 or Paper 4.

Paper Type of paper Duration Marks

1 Multiple Choice 1 hour 40

2 Theory 1 hour 30 minutes 75

4 Alternative to

practical

1 hour 30


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(continued)

Paper 1 Theory (1 h, 40 marks)

A paper consisting of 40 compulsory

multiple choice items of the simpledirect choice' type.

A copy of the Periodic Table will be

printed as part of this Paper.


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(continued)

Paper 2 Theory (1 h 30 min, 75 marks)consisting of two sections

Candidates will answer on the QuestionPaper.

A copy of the Periodic Table will be

printed as part of this Paper.


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(continued)


Section A45 marks

Compulsory, structured questions of

variable mark value.


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(continued)


Section B - 30 marks

4 questions each of 10 marks

Attempt any 3 questions.


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(continued)

Paper 4Alternative to Practical (1 h, 30 marks)

Marked out of 60 and then scaled to a mark

out of 30

Candidates will answer on the Question

Paper.

A written paper of compulsory short-answerand structured questions designed to test

familiarity with laboratory practical

procedures.


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(continued)


Questions may be set requiring candidates

to:(a) record readings from diagrams of

apparatus;

(b) describe, explain, comment on orsuggest experimental arrangements,

techniques and procedures;


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(continued)

Paper 4 Alternative to Practical (1 h, 30 marks)

(c) complete tables of data and/or plot

graphs;(d) interpret, draw conclusions from

and evaluate observations and

experimental (including graphical)data;


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(continued)


(e) describe tests for gases, ions,oxidising and reducing agents and/ordraw conclusions from such tests;


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(continued)

Paper 4 Alternative to Practical (1 h, 30 marks)

Candidates may also be required to

perform simple calculations.

The Qualitative Analysis Notes areNOT

provided.


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(continued)

Weighting of Assessment Objectives

Theory Papers (Papers 1 and 2)

A Knowledge with understanding,~ 65% of the marks with ~ allocated

to recall.

B Handling information and solving

problems,

~ 35% of the marks.


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(continued)

Weighting of Assessment Objectives

Practical Assessment (Papers 3 and 4)C Experimental skills and investigations,

Carries about 20% of the marks for the

subject.


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SUBJECT CONTENT

Most of the objectives specified in the

syllabus relate to Knowledge with

understanding, although some indicationhas been given as to where the skills of

Handling information and solving problems

may be developed.


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SUBJECT CONTENT

Some of the marks are allocated to these

higher thinking' skills.

Students should therefore be given

practice at dealing with unfamiliar

situations so that these higher thinking

skills can be developed.


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It is important that, throughout the course,

attention should be drawn to:

(i) the finite life of the world'sresources and economic and

environmental issues relating to

recycling, renewable energy andconservation;

SUBJECT CONTENT (continued)


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(ii) economic considerations in thechemical industry, such as the

availability and cost of raw

materials and energy;

(iii) the social, environmental, health

and safety issues relating to the

use of chemicals in the laboratory,

in the home and in industry;


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(iv) the importance of chemicals in

industry and in everyday life.


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MATHEMATICAL REQUIREMENTS

Calculators may be used in all parts of the

examination, providing they are in

accordance with the regulations stated in the

"UCLES Handbook for Centres" (General

Certificate of Education).


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(continued)

Candidates should be able to:

1. add, subtract, multiply and divide;

2. use averages, decimals, fractions,percentages, ratios and reciprocals;

3. recognise and use standard notation;

4. use direct and inverse proportion;

5. use positive, whole number indices;


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(continued)

6. draw charts and graphs from given

data;

7. interpret charts and graphs;8. select suitable scales and axes for

graphs;

9. make approximate evaluations ofnumerical expressions;


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(continued)

10. recognise and use the relationshipbetween length, surface area and

volume, and their units on metricscales;

11. solve equations of the form x = yz

for any one term when the other twoare known;


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(continued)

12. comprehend and use the

symbols/notations , , /, ;

13. comprehend how to handlenumerical work so that significant

figures are neither lost

unnecessarily nor used beyond whatis justified.


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GLOSSARY OF TERMS USED IN

CHEMISTRY PAPERS

1. Define (the term(s)...) is intended

literally. Only a formal statementor equivalent paraphrase being

required.


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GLOSSARY OF TERMS

(continued)

2. What do you understand by/What is

meant by (the term(s)...) normally implies that

a definition should be given, together with

some relevant comment on the significance or

context of the term(s) concerned, especially

where two or more terms are included in the

question. The amount of supplementarycomment intended should be interpreted in the

light of the indicated mark value.


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GLOSSARY OF TERMS

(continued)

3. State implies a concise answer with

little or no supporting argument, e.g. a

numerical answer that can be obtained

by inspection.

G OSSA O S


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GLOSSARY OF TERMS

(continued)

4. List requires a number of points,

generally each of one word, with no

elaboration. Where a given number of

points is specified, this should not be

exceeded.

GLOSSARY OF TERMS


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GLOSSARY OF TERMS

(continued)

5. Explain may imply reasoning or some

reference to theory, depending on the

context.


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GLOSSARY OF TERMS (continued)

6. Describe requires candidates to state inwords (using diagrams where appropriate)

the main points of the topic. It is often

used with reference either to particularphenomena or to particular experiments.

In the former instance, the term usually

implies that the answer should includereference to (visual) observations

associated with the phenomena.

GLOSSARY OF TERMS


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GLOSSARY OF TERMS

(continued)

In other contexts, describe and give an

account of should be interpreted more

generally, i.e. the candidate has greater

discretion about the nature and the

organisation of the material to be

included in the answer. Describe andexplain may be coupled in a similar

way to state and explain.

GLOSSARY OF TERMS


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GLOSSARY OF TERMS

(continued)

7. Discuss requires candidates to give a

critical account of the points involved

in the topic.

8. Outline implies brevity, i.e. restricting

the answer to giving essentials.

GLOSSARY OF TERMS


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GLOSSARY OF TERMS

(continued)

9. Predict or deduce implies that the

candidate is not expected to produce the

required answer by recall but by making

a logical connection between other

pieces of information. Such information

may be wholly given in the question or

may depend on answers extracted in an

early part of the question.

GLOSSARY OF TERMS


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GLOSSARY OF TERMS

(continued)

10. Comment is intended as an open-ended

instruction, inviting candidates to recall

or infer points of interest relevant to thecontext of the question, taking account

of the number of marks available.

GLOSSARY OF TERMS


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GLOSSARY OF TERMS

(continued)

11. Suggest is used in two main contexts, i.e.

either to imply that there is no unique

answer (e.g. in chemistry, two or more

substances may satisfy the given conditions

describing an unknown), or to imply that

candidates are expected to apply their

general knowledge to a novel situation,one that may be formally not in the

syllabus.

GLOSSARY OF TERMS


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GLOSSARY OF TERMS

(continued)

12. Find is a general term that may variously

be interpreted as calculate, measure,

determine etc.13. Calculate is used when a numerical

answer is required. In general, working

should be shown, especially where twoor more steps are involved.

GLOSSARY OF TERMS


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GLOSSARY OF TERMS

(continued)

14. Measure implies that the quantity

concerned can be directly obtained

from a suitable measuring instrument,e.g. length, using a rule, or angle, using

a protractor.

GLOSSARY OF TERMS


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GLOSSARY OF TERMS

(continued)

15. Determine often implies that the

quantity concerned cannot be measured

directly but is obtained by calculation,substituting measured or known values

of other quantities into a standard

formula, e.g. relative molecular mass.

GLOSSARY OF TERMS


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GLOSSARY OF TERMS

(continued)

16. Estimate implies a reasoned order of

magnitude statement or calculation of

the quantity concerned, making suchsimplifying assumptions as may be

necessary about points of principle and

about the values of quantities nototherwise included in the question.

GLOSSARY OF TERMS


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GLOSSARY OF TERMS

(continued)

17. Sketch, when applied to graph work,

implies that the shape and/or position of

the curve need only be qualitatively

correct, but candidates should be aware

that, depending on the context, some

quantitative aspects may be looked for,

e.g. passing through the origin, having an

intercept, asymptote or discontinuity at a

particular value.

GLOSSARY OF TERMS


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GLOSSARY OF TERMS

(continued)

In diagrams, sketch implies that a

simple, freehand drawing is acceptable:

nevertheless, care should be taken overproportions and the clear exposition of

important details.

GLOSSARY OF TERMS


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GLOSSARY OF TERMS

(continued)

18. Construct is often used in relation to

chemical equations where a candidate

is expected to write a balanced equation,not by factual recall but by analogy or

by using information in the question.


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Special Note

Units, significant figures. Candidatesshould be aware that misuse of units and/orsignificant figures, i.e. failure to quote units

where necessary, the inclusion of units inquantities defined as ratios or quotinganswers to an inappropriate number of

significant figures, is liable to be penalised.

chemistry 2005 for teachers

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