Six-mark questions
Six-mark questions are extended open response questions. These require longer answers than the structured questions that have fewer marks. It is wise to plan your answer first by making some notes. This will help you to include all the key points.
To gain full marks, you need to:
- support explanations using scientific knowledge and understanding
- use appropriate scientific words
- write clearly and link ideas in a logical way
- maintain a sustained line of reasoning
Writing six-mark answers with Dr Alex Lathbridge
Listen to the full series on BBC Sounds.
How to write six-mark answers in your science GCSE exams.
Six-mark questions often use these command words:
- Describe means you should recall facts, events or processes accurately. You might need to give an account of what something looked like, or what happened.
- Explain means you need to make something clear, or state the reasons for something happening.
- Compare means you need to describe similarities and differences between things. If you are asked to compare X and Y, write down something about X and something about Y, and give a comparison. Do not just write about X only or Y only.
- Evaluate means you must use information supplied, or your own knowledge, to consider the evidence for and against or to identify strengths and weaknesses. You must then complete your answer with a conclusion, stating which is better and why, for example.
Six-mark questions may be synoptic questions, which 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 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
Question
The table shows the ability of different substances to conduct electricity.
| Substance | Conducts electricity |
| Solid calcium chloride | No |
| Molten calcium chloride | Yes |
| Diamond | No |
| Zinc | Yes |
| Substance | Solid calcium chloride |
|---|---|
| Conducts electricity | No |
| Substance | Molten calcium chloride |
|---|---|
| Conducts electricity | Yes |
| Substance | Diamond |
|---|---|
| Conducts electricity | No |
| Substance | Zinc |
|---|---|
| Conducts electricity | Yes |
Explain these results by referring to the structures of the substances.
[6 marks]
Your answer can include any of the following:
- solid calcium chloride contains ions/cations/anions which are charged particles
- solid calcium chloride does not conduct because charged particles are not free to move because they are held together by strong electrostatic forces/ionic bonds in lattice
- molten calcium chloride conducts because ions/cations/anions are present which are charged particles and are free to move
- the ions have separated, and move to the electrode of opposite charge
- diamond does not conduct because it is a giant molecular covalent structure with no free electrons
- outer electrons of carbon atoms are used in bonding
- zinc metallic structure consists of delocalised free electrons which can move between layers of metals atoms/cations
Sample question 2 - Foundation
Question
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 can include any of 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/forces of attraction between particles break/are overcome
Sample question 3 - Higher
Question
The table shows the melting points of different substances.
| Substance | Melting point |
| Sodium chloride | 801°C |
| Water | 0°C |
| Diamond | 3730°C |
| Substance | Sodium chloride |
|---|---|
| Melting point | 801°C |
| Substance | Water |
|---|---|
| Melting point | 0°C |
| Substance | Diamond |
|---|---|
| Melting point | 3730°C |
Explain these results by referring to the structures of the substances.
[6 marks]
Your answer can include any of the following:
- sodium chloride contains ions in a regular lattice
- there are electrostatic forces of attraction between oppositely charged ions
- the forces/ionic bonds are strong
- large amounts of energy are needed to overcome/break these forces/bonds
- water exists as simple molecules
- there are weak intermolecular forces between molecules
- less energy needed to overcome these forces
- diamond exists as giant molecules
- there are covalent bonds between atoms
- many strong covalent bonds
- a very large amount of energy is needed to break bonds
Sample question 4 - Higher
Question
The kinetic particle theory describes the arrangement, movement and relative energy of particles in the three states of matter.
Figure 1 shows a model that represents the particles in solids, liquids and gases.
Figure 1
Evaluate the strengths and weaknesses of this model.
[6 marks]
Your answer can include any of 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
