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Acids, bases and titration — Question 21

QCAA 2025, Paper 1 · 2 marks

Q21 · 2025 · Paper 1Unclassified2 marks

QUESTION 21 (2 marks)

An unknown acid, HA, undergoes 1.3% ionisation in an aqueous solution.

HA(aq) + H2O(l) ⇌ H3O+(aq) + A−(aq)

a) Classify HA as a strong or weak acid.

[1 mark]

b) Explain whether HA is a monoprotic or polyprotic acid.

[1 mark]

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