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.

Most questions on exam papers have mark schemes that give key points that are given marks. The six-mark questions are marked differently - they use a levels-based mark scheme. This type of mark scheme is used because these questions are more open-ended. 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.

Answers are placed in three marking bands:

  • 1 to 2 marks for answers showing limited content and reasoning and with significant omissions.
  • 3 to 4 marks for answers that give some relevant points, with linking and reasoning and with fewer omissions.
  • 5 to 6 marks for answers that link most of the relevant points, with good links and reasoning. They will have few, if any, omissions.

Questions courtesy of Eduqas.

Sample question 1 - Higher


Explain, using particle theory, how the rate of a chemical reaction depends on concentration and temperature. [6 marks]

Your answer should include the following:

  • for a chemical reaction to take place the reactant particles must collide
  • increasing the concentration increases the number of particles in the same volume
  • this gives a greater chance of the particles colliding, giving an increase in the rate of the reaction
  • as the temperature increases the reactant particles are moving faster
  • this increases the chance of a collision
  • at higher temperature the particles also have higher energy
  • this increases the possibility of having sufficient energy during collision to overcome the activation energy and become a 'successful collision'
  • therefore increasing the temperature also increases the speed of a reaction