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...''

'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.

This page contains AQA material which is reproduced by permission of AQA.

Sample question 1 - Foundation


The information below is about the properties of solids and gases:


  • have a fixed shape
  • are difficult to compress (to squash)


  • will spread and fill the entire container
  • are easy to compress (to squash)

Use your knowledge of kinetic theory to explain the information given in the box. [6 marks]

You should consider:

  • the spacing between the particles
  • the movement of individual particles
  • the forces between the particles

In a solid the particles are close together. This makes solids very difficult to compress. In a solid there are strong bonds between the particles that keep the particles in a fixed position. This is why solids have a fixed shape. In a gas the particles are far apart with a lot of empty space between them. This is why gases are easy to compress. The particles are moving randomly in all directions at high speed, which is why a gas will spread and fill the entire container.

A strong answer will mention the behaviour of the particles in both solids and liquids and link this behaviour to the properties described in the box. It may include the following points:


  • (particles) close together
  • (so) no room for particles to move closer (so hard to compress)
  • vibrate about a fixed point
  • strong forces of attraction (at a distance)
  • forces become repulsive if the particles get closer
  • particles strongly held together/not free to move around (shape is fixed)


  • (particles) far apart
  • space between particles (so easy to compress)
  • move randomly
  • negligible/no forces of attraction
  • spread out in all directions (to fill the container)


Sample question 2 - Higher


There is solid ice on a car’s rear window.

The glass window contains an electrical heating element.

An arrangement of particles for solid ice, which melts into an arrangement of particles for liquid water.

Use the particle model above to describe how the heating element causes the arrangement of the ice particles to change as the ice melts.

You should include a description of how the particles are arranged in the solid ice and in the water. [6 marks]

The electric current in the wire causes heating which increases the temperature of the metal wires and the ice. In the solid ice, the arrangement of particles is regular and they vibrate about a fixed position. When the solid melts, the internal energy of the ice increases, increasing the temperature to melting point and the particles vibrate faster. Eventually, the particles vibrate fast enough to break the intermolecular bonds and move randomly in an irregular, liquid, arrangement.

A strong answer will be clearly worded with good use of scientific key words. It may include the following points:

  • current in the wire causes heating
  • increases temperature of the metal wires/ice


  • arrangement of particles is regular
  • particles vibrate about a fixed position


  • internal energy of the ice increases, increasing the temperature to melting point
  • so (as the temperature increases) particles vibrate faster
  • eventually particles vibrate fast enough to break free from the (strong) bonds
  • therefore the arrangement of particles becomes irregular


  • arrangement of particles is irregular
  • particle movement (translational) is random