A-LevelChemistryEquilibriaOct/Nov 2017Paper 1 Q341 Mark
Methanoic acid, HCO2H, and hydrocyanic acid, HCN, can both behave as acids. A solution of methanoic acid has a lower pH than a solution of hydrocyanic acid of the same concentration. Which statements explain this? 1 HCO2H molecules dissociate more fully than HCN molecules do. 2 Each HCO2H molecule has two hydrogen atoms; each HCN molecule only has one. 3 Methanoic acid is a weaker acid than hydrocyanic acid.
A1, 2 and 3 are correct
B1 and 2 only are correct
C2 and 3 only are correct
D1 only is correct
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The correct answer is D. This question tests the candidate's understanding of equilibria within the Chemistrysyllabus. The examiner's mark scheme requires...
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