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A-LevelChemistryGroup 179701/12 · May/June 2021 · 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

D: ClO⁻

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About this question

Topic
Group 17, A-Level Chemistry (syllabus 9701). Multiple choice, 1 mark.
Source
A-Level Chemistry, May/June 2021 Paper 1 Variant 2, question 17.

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