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Chemistry

INTRODUCTION

An extended essay in Chemistry provides a candidate with an opportunity to personally investigate a particular aspect of the materials of our environment. Such Extended Essays should be characterised by a particular emphasis within a more general set of scientific criteria. An Extended Essay in Chemistry may be literature/survey based, theoretical model-based or experimental data-based. Whichever category is chosen the student should ensure that sufficient data will be available for evaluation and that the topic can be researched accurately using locally available resources.Students who choose to write a literature/survey-based Extended Essay should ensure that their Extended Essay clearly shows its chemical basis, essays written at the level of a newspaper or news magazine article are unlikely to achieve a high mark. Students are encouraged to undertake experimental work as part of their research even if it is not compulsory. Any experimental work should be described in sufficient detail to allow the work to be repeated by others. Data collected from an experiment designed by the student is of little value unless it is analysed, using appropriate scientific techniques, evaluated and possibly compared with appropriate models. It is possible to use data collected elsewhere as a primary source. In such cases, the element of personal analysis and evaluation is important. In a Chemistry Extended Essay the student should show an understanding of the results obtained and be able to interpret them with reference to the research question posed. Some explanation may be necessary to account for anomalies, bu this should form a minor part of the discussion. Where a hypothesis has been tested, the outcome may indicate that it may be necessary to consider modifying it. Alternatively, some assessment of the outcome(s) could be made in a future, or wider context. Aside from incorporating chemical theory, it is expected that techniques/procedures which are characteristic of chemical enquiry will be included as appropritae to the topic being investigated.

CHOICE OF TOPIC

It is essential that the Extended Essay has a clear chemical emphasis ans is not biased towards another subject. Although similar criteria apply to all Extended Essays in the Sciences, for an Extended Essay submitted in Chemistry, the topic chosen must allow an approach which distinctively involves Chemistry. Where a topic might be approached from different viewpoints, the treatment of the material must be approached from a cheical perspective. Some topics may be unsuitable fro investigation because of safety issues.

The following examples of titles for Chemistry Extended Essays are intended as guidance only.

Electrolytic determination of Avogadro's Number is better than Avogadro's Number.

Analysis of Vitamin-C content of selected orange drinks is better than A study of Vitamin C.

Spectrophotometric determination of trace amounts of lead in drinking water is better than Water analysis.

ASSESSMENT CRITERIA

J To what extent does the essay address the principles and issues which govern the properties and behabiour of the materials of our environment?

Achievement Level

0 There is no evidence of any principles or issues relating to chemistry.

1 Some principles or issues relating to chemistry are evident but are given no emphasis.

2 Some of the relevant principles or issues relating to chemistry are evident but are given limited emphasis.

3 Most of the relevant principles or issues relating to chemistry are evident and are given emphasis.

4 All of the relevant principles or issues relating to chemistry are included and are given strong emphasis.

K To what extent are scientific techniques appropriate to chemistry (experimental design/theoretical development/sources) accessed?

Achievement Level

0 No relevant scientific techniques are apparent.

1 Scientific techniques are relevant to the research question but show minimal competence.

2 Scientific techniques are relevant to the research question, are carefully chosen and accurately completed but are applied in a completely routine manner.

3 Scientific techniques are relevant to the research question, are carefully chosen and accurately completed, and there is some evidence of an original or personal approach to their application.

4 Scientific techniques are relevant to the research question, are carefully chosen and accurately completed, and consistently show evidence of an original or personal approach to their application.

L To what extent are the limitations surrounding the chemical research analysed?

Achievement Level

0 There is no awareness of uncertainties, approximations, quality of experimental design or quality of sources accessed. There are no explanations, confirmations and refutations.

1 Uncertainties, approximations, quality of experimental design or quality of sources accessed are briefly mentioned. There is no supporting evidence for explanations, confirmations and refutations.

2 There is a clear awareness of uncertainties, approximations, quality of experimental design or quality of sources accessed. Explanations, confirmations and refutations are inadequately supported.

3 There is a clear awareness but limited analysis of uncertainties, approximations, quality of experimental design or quality of sources accessed. Explanations, confirmations and refutations are not wholly supported.

4 Uncertainties in experimental data are analysed and approximations in models are accounted for. Inadequate experimental design or any systematic error is exposed. The quality of sources accessed is verified by secondary sources or by direct calculations. Explanations, confirmations and refutations are supported by these analyses.
IB homepage Extended Essay Homepage Subject grading criteria General grading criteria General guidelines

J	To what extent does the essay address the principles and issues which govern the properties and behabiour of the materials of our environment?
Achievement Level
0	There is no evidence of any principles or issues relating to chemistry.
1	Some principles or issues relating to chemistry are evident but are given no emphasis.
2	Some of the relevant principles or issues relating to chemistry are evident but are given limited emphasis.
3	Most of the relevant principles or issues relating to chemistry are evident and are given emphasis.
4	All of the relevant principles or issues relating to chemistry are included and are given strong emphasis.

K	To what extent are scientific techniques appropriate to chemistry (experimental design/theoretical development/sources) accessed?
Achievement Level
0	No relevant scientific techniques are apparent.
1	Scientific techniques are relevant to the research question but show minimal competence.
2	Scientific techniques are relevant to the research question, are carefully chosen and accurately completed but are applied in a completely routine manner.
3	Scientific techniques are relevant to the research question, are carefully chosen and accurately completed, and there is some evidence of an original or personal approach to their application.
4	Scientific techniques are relevant to the research question, are carefully chosen and accurately completed, and consistently show evidence of an original or personal approach to their application.

L	To what extent are the limitations surrounding the chemical research analysed?
Achievement Level
0	There is no awareness of uncertainties, approximations, quality of experimental design or quality of sources accessed. There are no explanations, confirmations and refutations.
1	Uncertainties, approximations, quality of experimental design or quality of sources accessed are briefly mentioned. There is no supporting evidence for explanations, confirmations and refutations.
2	There is a clear awareness of uncertainties, approximations, quality of experimental design or quality of sources accessed. Explanations, confirmations and refutations are inadequately supported.
3	There is a clear awareness but limited analysis of uncertainties, approximations, quality of experimental design or quality of sources accessed. Explanations, confirmations and refutations are not wholly supported.
4	Uncertainties in experimental data are analysed and approximations in models are accounted for. Inadequate experimental design or any systematic error is exposed. The quality of sources accessed is verified by secondary sources or by direct calculations. Explanations, confirmations and refutations are supported by these analyses.