O-LevelChemistryStoichiometry5070/12 · May/June 2018 · Q241 Mark

The compounds shown can be used as nitrogenous fertilisers. Which compound has the lowest percentage by mass of nitrogen?

A(NH₂)₂CO [Mᵣ: 60]

B(NH₄)₂SO₄ [Mᵣ: 132]

C(NH₄)₃PO₄ [Mᵣ: 149]

DNH₄NO₃ [Mᵣ: 80]

✓ Correct answer

B: (NH₄)₂SO₄ [Mᵣ: 132]

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Topic: Stoichiometry, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source: O-Level Chemistry, May/June 2018 Paper 1 Variant 2, question 24.

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