O-LevelChemistryStoichiometry5070/12 · Oct/Nov 2023 · Q101 Mark

Chrome alum is the common name for a salt which has the formula CrK(SO4)2. What is the percentage by mass of chromium in chrome alum?

A17.3

B18.4

C20.7

D21.3

✓ Correct answer

B: 18.4

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Topic: Stoichiometry, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source: O-Level Chemistry, Oct/Nov 2023 Paper 1 Variant 2, question 10.

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