O-LevelChemistryStoichiometry5070/11 · Oct/Nov 2011 · Q111 Mark

What is the ratio of the number of molecules in 71 g of gaseous chlorine to the number of molecules in 2 g of gaseous hydrogen? [Relative atomic masses Aᵣ (atomic weights): H, 1: Cl, 35.5]

A1:1

B1:2

C2:1

D71:2

✓ Correct answer

A: 1:1

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Topic: Stoichiometry, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source: O-Level Chemistry, Oct/Nov 2011 Paper 1 Variant 1, question 11.

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