The newest 6 of 6 written questions. Open one to see it on the real paper.
The treatment of the domestic water supply uses four processes: sedimentation, filtration, use of carbon and then chlorination. Describe the purpose of three of these processes. sedimentation use of carbon chlorination
See it on the paper →Domestic water is treated so that it is pure enough to drink. Draw one line from each treatment to show why it is used. treatment why it is used chlorination to remove solids sedimentation and filtration to remove tastes and odours use of carbon to kill microbes
See it on the paper →Used in the treatment of the water supply.
See it on the paper →Carbon dioxide dissolves in oceans, acidifying them. State two sources of water pollution.
See it on the paper →The treatment of a water supply uses filtration and chlorination. Give a reason for using filtration and chlorination. filtration chlorination
See it on the paper →Water must be treated so that it is safe to drink. Draw lines to link each stage in the water treatment process to the reason why it is used. stage reason kills microbes filtration allows larger solid particles to settle out chlorination traps finer particles using sand
See it on the paper →Candidates displayed a very good understanding of domestic water treatment.
— Examiner report, May/June 2025, 0654/41 Q5(d) (Cambridge)
Many vague answers were given. The purpose of filtration is to remove solid particles and the purpose of chlorination is to kill microbes, etc.
— Examiner report, October/November 2023, 0654/33 Q2(b) (Cambridge)
Almost all candidates knew that chlorination kills microbes, however fewer identified that filtration traps finer particles using sand. Any line drawn indicating that filtration allows larger solid particles to settle out was ignored.
— Examiner report, October/November 2022, 0654/43 Q8(a) (Cambridge)
Past papers, syllabus and examiner reports © UCLES (Cambridge University Press & Assessment). Questions are matched to topics from the official syllabus. AssessPro is independent and not endorsed by Cambridge.