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

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


Describe the structure of an atom, including properties of its subatomic particles. [6 marks]

Your answer can include any of the following:

  • Nucleus surrounded by electrons.
  • Electrons arranged in shells. [1]
  • Nucleus contains protons and neutrons. [1]
  • Number of protons and electrons is the same. [1]
  • Protons are positively charged, electrons are negatively charged, neutrons are neutral. [1]
  • Overall charge on an atom is zero. [1]
  • Protons and neutrons have the same mass, electrons are very much lighter particles. [1]
  • Most of the mass is concentrated in the nucleus. [1]
  • Nucleus is very small compared to the overall size of an atom. [1]

Sample question 2 - Foundation


Two elements in group 1 of the periodic table are lithium and sodium.

Very small pieces of lithium and sodium were reacted separately with water.

Describe the similarities and differences in what is seen and in the products of the reactions. [6 marks]

Your answer can include any of the following:

Similarities - both:

  • float on the surface [1]
  • move around [1]
  • effervescence/bubble/fizz [1]
  • decrease in size/disappear/dissolve [1]
  • produce hydrogen/H2 [1]
  • produce (metal) hydroxide/LiOH and NaOH [1]
  • produce alkaline solution/solution with pH greater than 7/add named indicator to the solution and correct colour change [1]
  • correct products shown in equations [1]


  • sodium more vigorous/more effervescence/moves faster [1]
  • melts [1]
  • forms ball/sphere [1]
  • produces a flame/catches fire/sparks [1]

Sample question 3 - Higher


In the periodic table, the group 7 elements and the group 0 elements are non-metals.

Compare the physical and chemical properties of the group 7 and group 0 elements. In your answer, use ideas about electronic structure to explain differences in chemical properties. [6 marks]

Physical properties:

  • group 0
    • all are in the gas state at room temperature
    • boiling points increase down group/with increasing relative atomic mass
  • group 7
    • chlorine is in the gas state at room temperature, bromine is in the liquid state, and is iodine in the solid state.
    • boiling points increase down the group/with increasing relative atomic mass

Chemical properties:

  • group 0
    • very unreactive because the atoms have stable electronic structures
  • group 7
    • very reactive because atoms have 7 electrons in outer shell
    • reactivity decreases going down the group
    • react vigorously with metals
    • a more reactive halogen can displace a less reactive halogen from an aqueous solution of its salt

Sample question 4 - Higher


Group 1 of the periodic table contains the alkali metals lithium, sodium and potassium.

The alkali metals show a pattern in their reactivity with water.

This pattern is shown when small pieces of lithium, sodium and potassium are added separately to water.

Describe the reactions and explain the pattern in reactivity. [6 marks]

Your answer can include any of the following:


  • effervescence/fizzing/bubbles
  • float/on surface
  • move
  • produce hydrogen (may be shown in word or balanced equation)
  • an alkaline/metal hydroxide solution (may be shown in word or balanced equation)
  • gets smaller/disappears/dissolves
  • reactivity increases with increasing atomic number/down the group/potassium effervesces more than sodium and lithium/potassium moves faster than sodium or lithium
  • sodium and potassium melt/form a (silver-coloured) ball
  • hydrogen burns when potassium/sodium react
  • potassium gives a lilac flame/sodium gives a yellow flame
  • universal indicator added to water turns blue/purple


  • (group 1 metals) react by losing one electron
  • electron is more easily lost with increasing atomic number/down the group
  • electron/ outer shell is further away from nucleus/atomic radius increases/there are more electron shells with increasing atomic number/down the group
  • more shielding (of outer electron)/less attraction between nucleus and outer electron/more shells between outer electron and nucleus with increasing atomic number/down the group