O-LevelChemistryStoichiometry5070/11 · May/June 2025 · Q131 Mark

100 cm³ of aqueous potassium hydroxide with a concentration of 1.00 mol/dm³ reacts with excess dilute sulfuric acid. 2KOH(aq) + H2SO4(aq) → K2SO4(aq) + 2H2O(l) 3.48 g of pure anhydrous potassium sulfate is produced. What is the percentage yield of potassium sulfate?

A5%

B10%

C20%

D40%

✓ Correct answer

D: 40%

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Topic: Stoichiometry, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source: O-Level Chemistry, May/June 2025 Paper 1 Variant 1, question 13.

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