Important Exam Advice
Important exam advice for sciences students.
You cannot score marks unless you write answers but this does not mean you should spend all the time writing in an examination. It is important to read the question carefully so that you know what to answer. By knowing what needs to be covered, you can produce an appropriate answer and spend less time writing. The most basic advice for being successful in examinations is to:
- read each question carefully and then answer it
- write to the point, being specific not vague.
|Calculate||A numerical answer is needed. You should show any working, especially when there are two or more steps in a calculation.|
e.g. Calculate the concentration of potassium hydroxide in the solution
|Deduce||This may be used in two ways:|
|Define||You need to state the meaning of something, e.g. reduction is gain of electrons; a hydrocarbon is a compound containing only hydrogen and carbon.|
|Describe||You need to state the main points about something (using labelled diagrams if this helps you), e.g. describe how metals and non-metals differ in their properties . You may also be asked to describe either|
observations, e.g. describe what you see when sodium reacts with water,
or how to do particular experiments, e.g. describe how to separate a mixture of coloured inks.
|Determine||You are expected to use a formula that you know to calculate a quantity, e.g. determine the relative molecular mass of ethanol.|
|Discuss||You have to write down points for and against an argument, e.g. discuss points for and against the use of petrol as a fuel.|
|Estimate||This may be used in two ways: i. You need to work out an approximate value for a quantity, based on your knowledge of theory and the information provided, e.g. estimate the boiling point of butanol.|
ii. For titrations, ‘estimate’ may also mean that you need to calculate an exact quantity, e.g. estimate the concentration of sodium hydroxide
|Explain||You have to give reasons for your answer OR refer to a particular theory, e.g. explain why reaction rate increases with temperature.|
|Find||This is a general term which can mean several similar things, such|
as calculate, measure, determine, etc.
|List||Write down a number of separate points. Where the number of points is stated in the question, you should not write more than this number,|
e.g. list three properties of metals.
|Outline||State the main points briefly, e.g. outline the process of extracting aluminium from pure aluminium oxide.|
|Predict||This can be used in two ways: i. You fi nd the answer by working out the patterns in the information provided and drawing logical conclusions from this. You may need to use information from tables and graphs and do chemical calculations, e.g. predict what will happen to the level of carbon dioxide if …|
ii. It may also mean giving a short answer stating what might happen next e.g. predict what you would see when X reacts with bromine water.
|State||You should give a short answer without going into any detail,|
e.g. state the name of the compound with the formula CuSO4. BUT, remember that ‘state the meaning of…’ is different. It is more
|Suggest||This may be used in two ways:|
i. There may be more than one correct answer to the question, e.g. after adding aqueous sodium hydroxide to the solution a white ppt was seen, suggest an ion that may be present.
ii. You are being asked to apply your general knowledge of chemistry or reasoning skills to a topic area that is not on the syllabus, e.g. applying ideas about reduction to a question on the extraction of zinc.
Much of what follows illustrates these points with regard to the papers you will take. There is no magic recipe for being successful in exams. You need to work hard in your study and prepare thoroughly. The advice is about making the most of what you can do in the exam and so allow you to obtain the best result.
- Read the question so that you understand exactly what is required before you start to answer. You must do what the question asks. We often use certain terms to make it clear what is required e.g. explain, describe, suggest. The meaning of these words can be found in the appendices section at the end of this document and also in the syllabus.
- Take careful note of how many marks there are for a question. Generally the number of marks indicates the number of points you need to cover in your answer.
- Provide what the question asks for. If a question asks for two examples, give two – extra wrong answers may lose you marks. ‘Describe what you observe’ requires you to write down what you see,
hear or feel (e.g. the test-tube gets hot).
- Write to the point. There is a lot of time wasted in exams by writing the same answer more than once and by including irrelevant material.
- Read over your answer and check for any contradictions.
- In calculations always show your working – even if your answer is wrong, you may get marks for your method. Give units when needed. Your answer should be given in the manner requested or to the
same number of significant figures as the data provided in the question. Make sure that you understand the difference between signifi cant fi gures and decimal places. For example the mass 11.445 g is to
5 signifi cant fi gures and 3 decimal places. If it was corrected to 4 signifi cant fi gures it would become 11.45 g and corrected to 3 signifi cant fi gures 11.4 g.
- When you draw diagrams, make sure they fill the space given on the paper and they are fully labelled.
- The correct spelling of a chemical name is not always required to obtain the mark as long as it cannot be mistaken for another. However, in questions where you are asked to select the names of chemicals or the like from a list, you are expected to get the spelling correct. Examples like writing ‘ammonium’ for ‘ammonia’ or ‘chlorine’ for ‘chloride’ will not be given credit because these are chemical mistakes.