Six mark questions are often the questions that people find the most difficult. In all longer answer questions, but especially the six mark ones, it is important that you plan your answer and not just rush into it. After all, you would plan an essay or short story before starting. Without a plan it is easy to stray away from the key point and lose marks, get steps in a process in the wrong order or forget key bits of information.
Six mark questions will start with command words such as 'describe' or 'explain'. The command words 'describe' and 'explain' can be confusing. If you are asked to describe a graph, you will be expected to write about its overall shape, whether it is linear or curved, the slope of gradients etc. If you are asked to explain why a pattern or trend is seen in a graph, you will be expected to use your science knowledge, not just say what you see (which is a description), eg 'The graph shows the number of radioactive nuclei decreases as time increases. It does this because…'.
'Explain how' and 'why' questions often have the word ‘because’ in their answer. 'Describe' questions don’t.
The number of marks per question part is given in this form ‘[6 marks]’. It is essential that you give as many different points in your answer as possible, linking these together. Often, you will be asked to compare two things: make sure that you include both in your answer otherwise, you are likely to limit your score to two marks out of six marks.
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The figure below shows a coil and a magnet. An ammeter is connected to the coil.
The ammeter has a centre zero scale, so that values of current going in either direction through the coil can be measured.
A teacher moves the magnet slowly towards the coil.
Explain why there is a reading on the ammeter. [6 marks]
There is a magnetic field around the magnet. The magnetic field moves when the magnet moves. As the magnet moves, the magnetic field lines cut through the coil. This induces a potential difference in the coil. A current is induced because the coil forms a complete circuit. 
Before starting a question of this type, it may be useful to list the scientific key terms to be included, eg magnetic field, coil, induced, potential difference, current. These can then be used to structure the answer as a sentence can introduce and link each term to the others.
The table gives data about two types of light bulb people may use in their homes.
|Type of light bulb||Energy efficiency (%)||Cost of one light bulb (£)||Average lifetime in hours (h)|
|Light Emitting Diode (LED)||32||11.70||36,000|
Both types of light bulb produce the same amount of light.
Evaluate, in terms of cost and energy efficiency, the use of the two types of light bulb. [6 marks]
Halogen bulbs are cheaper to buy than LED bulbs but they do not last as long. You would need to buy 18 halogen bulbs, costing £35.10, to last as long as a single LED bulb, costing £11.70. Even though the LED bulbs are more expensive, fewer of them are needed and the overall cost will be lower. LED bulbs are also more efficient, meaning they waste less energy to the surroundings.
A strong answer will compare both types of light bulb and conclude which light bulb would be the best to use.
Examples of the points made in a good answer: