A-LevelChemistryGroup 17May/June 2021Paper 1 Q171 Mark
Chlorine gas is widely used to treat contaminated water. When chlorine is added to water, which chemical species present is responsible for killing bacteria?
AClO₂⁻
BCl⁻
CHCl
DClO⁻
✓ Correct Answer
The correct answer is D. This question tests the candidate's understanding of group 17 within the Chemistrysyllabus. The examiner's mark scheme requires...
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Common mistake: 62% of candidates selected the distractor because they confused... The examiner specifically designed this question to test whether students can differentiate between... To secure full marks, candidates must demonstrate...
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