What is the mass of 3 mol of NH₃? (molar mass 17 g/mol)
Answer and explanation
Correct answer: A. 51 g
- Step 1: Mass = moles × molar mass. Step 2. 3 × 17 = 51 g. Answer: 51 g. Why not the others: 5.667 g is what you get if you divide the molar mass by the moles. 20 g is what you get if you add the numbers. 5.1 g is what you get if you misplace the decimal point.
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