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A-LevelChemistryNitrogen and sulfur9701/12 · Feb/Mar 2020 · Q151 Mark

Solid ammonium nitrate is put into a test-tube and solution X is added to it. The resulting mixture is warmed and the gas given off is tested with damp red litmus paper. The litmus paper changes colour from red to blue. What could be the identity of X and its role in the reaction?

Aidentity of X: NaOH(aq), role of X: proton donor
Bidentity of X: NaOH(aq), role of X: proton acceptor
Cidentity of X: HCl(aq), role of X: proton donor
Didentity of X: HCl(aq), role of X: proton acceptor

✓ Correct answer

B: identity of X: NaOH(aq), role of X: proton acceptor

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About this question

Topic
Nitrogen and sulfur, A-Level Chemistry (syllabus 9701). Multiple choice, 1 mark.
Source
A-Level Chemistry, Feb/Mar 2020 Paper 1 Variant 2, question 15.

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