Six-mark questions
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鈥'.
'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.
Writing six-mark answers with Dr Alex Lathbridge
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How to write six-mark answers in your science GCSE exams.
Sample question 1 - Foundation and Higher
Question
A student investigates how the extension of a spring varies when he hangs different loads from it. Write a plan for the student's investigation.
Your plan should include details of how the student can make accurate measurements.
You may add to the diagram to help your answer. [6 marks]
This question has been written by a Bitesize consultant as a suggestion to the type of question that may appear in an exam paper.
The independent variable is the load 鈥 it is changed by adding masses one at a time. The weight can be found using a Newton metre. The dependent variable is the length of the spring. The length can be measured using a ruler. The extension should then be calculated by subtracting the original length of the un-stretched spring. To ensure the measurements are accurate, repeat measurements of mass and length can be taken and a mean calculated.
Plan the key points which you should include in your answer. You should discuss the independent and dependent variables and what instrument would be used to measure them. You should explain how the results will be processed and then analysed. Remember to consider how the student can make accurate measurements.
Sample question 2 - Higher
Question
The figure below shows the submarine stationary and submerged at a depth of 10 m.
Explain how pumping water into and out of the buoyancy tank affects the depth of the submarine below the surface. [6 marks]
Edexcel question courtesy of Pearson Education Ltd.
Upthrust is the force on the submarine in the water submerged in a fluid. Upthrust is equal to the weight of water displaced by the submarine. Upthrust on the submarine and its weight act in opposite directions. The volume of the submarine is fixed so the upthrust on the submarine is constant. Increasing the volume of water in tanks increases the weight of the submarine but does not affect the upthrust. If weight increases to become greater than upthrust, there is a resultant downward force on the submarine so the submarine sinks. Decreasing the volume of water in tanks decreases the weight of submarine. If weight decreases to become less than upthrust there is a resultant upward force on the submarine so the submarine rises.
Plan the key points which you should include in your answer. State the forces acting on the submarine, where they come from and their directions. Remember, if the submarine is stationary, the forces must be balanced. Consider what happens to the size of the forces when water is pumped into the buoyancy tank and then the effect on the motion of the submarine.