At a chemical plant in Trinidad, ammonia (NH₃) is produced for fertiliser. How many moles of ammonia are present in 68 g of the compound? (N = 14, H = 1)

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Question

At a chemical plant in Trinidad, ammonia (NH₃) is produced for fertiliser. How many moles of ammonia are present in 68 g of the compound? (N = 14, H = 1)

Accepted Answer

4 mol — Award 1 mark for correct calculation. Molar mass of NH₃ = 14 + (3 × 1) = 17 g/mol. Moles = 68 ÷ 17 = 4 mol. A is incorrect — this would be 34 g. C is incorrect — this would be 8.5 g. D is incorrect — student confused molar mass with number of moles.

Answer

2 mol

Answer

17 mol

Answer

0.5 mol

Answer

4 mol

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