O-LevelChemistryAcids, Bases & Salts5070/11 · May/June 2016 · Q21 Mark

Four gas jars each contain one of the gases ammonia, chlorine, hydrogen chloride and oxygen. A strip of damp blue litmus paper and a strip of damp red litmus paper are placed in each jar. In which gas jar will both the damp blue litmus paper and the damp red litmus paper change colour?

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Aammonia

Bchlorine

Chydrogen chloride

Doxygen

✓ Correct answer

B: chlorine

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Topic: Acids, Bases & Salts, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source: O-Level Chemistry, May/June 2016 Paper 1 Variant 1, question 2.

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