Six-mark questions

Six-mark questions are extended open response questions. These require longer answers than the structured questions. It is wise to plan your answer rather than rushing straight into it, otherwise you may stray away from the key points.

To gain full marks, you need to:

  • support explanations using scientific knowledge and understanding
  • use appropriate scientific words and terms
  • write clearly and link ideas in a logical way
  • maintain a sustained line of reasoning, rather than getting lost or bogged down

Six-mark questions often use these command words:

  • Describe - you need to give an account but no reason
  • Explain - you must give reasons or explanations
  • Devise - you must plan or invent a procedure using your scientific knowledge and understanding
  • Evaluate - you must review information, including identifying strengths and weaknesses, and make a supported conclusion

Six-mark questions may be synoptic questions. These questions bring together ideas from two or more topics. For example, a question about fertilisers could include ideas about covalent substances, acids and alkalis, chemical calculations, and effects on the environment.

The answers shown here give marking points as bullet points. You do not usually need to include all of them to gain six marks, but you do need to write in full sentences, linking them logically and clearly.

These questions have been written by Bitesize consultants as suggestions to the types of questions that may appear in an exam paper.

Sample question 1 - Foundation


Describe the arrangement and movement of particles in each of the three states of matter. Explain what happens to the particles in a liquid during boiling. [6 marks]

Your answer should include the following:

  • Particles in solids are close together and regularly arranged.
  • Particles in solids vibrate about fixed positions.
  • Particles in liquids are close together and randomly arranged.
  • Particles in liquids move around each other.
  • Particles in gases are far apart and randomly arranged.
  • During boiling, energy is transferred to particles.
  • Bonds between particles break/are overcome.


Sample question 2 - Higher


Fresh water can be stored in reservoirs in the UK. Describe how water from a reservoir can be made potable. In your answer, include the meaning of potable. [6 marks]

Your answer should include the following:

  • Potable means safe to drink.
  • Screens used to remove large objects such as branches and leaves.
  • A coarse filter bed is used to remove larger insoluble grit particles.
  • Aluminium sulfate used to clump small particles together.
  • Allow sedimentation to occur (larger insoluble particles sink). Fine filter to remove smaller insoluble particles.
  • Chlorine added to kill harmful microorganisms.
  • Protons and neutrons have the same mass, electrons are much lighter particles.
  • Most of the mass is concentrated in the nucleus.
  • Nucleus is very small compared to the overall size of an atom.


Sample question 3 - Foundation


Food colourings contain a mixture of water soluble dyes. Devise a method to separate the dyes in a sample of food colouring. Explain how this method works. [6 marks]

Your answer should include the following:

  • Add a spot of food colouring, in a line, near the bottom of a piece of chromatography paper/filter paper.
  • Place the paper in a container with some water/solvent.
  • Allow the water/solvent to travel through the paper.
  • Remove the paper before the water/solvent reaches the top of the paper, and allow it to dry.
  • The spots on the paper will indicate the number and type of dyes present.
  • Paper chromatography uses a mobile phase (the solvent/water).
  • And a stationary phase (contained on the paper).
  • Forces of attraction between the dyes and these phases cause the dyes to move at different rates over the paper.
  • This depends on solubility of the dyes in mobile and static phase.


Sample question 4 - Higher


The kinetic particle theory describes the arrangement, movement and relative energy of particles in the three states of matter. The diagrams show a model that represents the particles in solids, liquids and gases.

Atomic states of solid, liquid and gas.

Evaluate the accuracy of this model. [6 marks]

Your answer should include the following:

Strengths include:

  • particles in solids and liquids are shown close together, but far apart in gases
  • particles in solids are shown regularly arranged, but randomly arranged in liquids and gases

Weaknesses include:

  • particles are shown in 2D only (and not in 3D)
  • particles in gases are too close together
  • the model is static/not moving
  • the relative energy of particles is not modelled
  • bonds/forces between particles are not modelled

Supported conclusion given, eg:

  • model is accurate for arrangements, but not for movement and relative energy of particles