What is the mass of 3 mol of HNO₃? (molar mass 63 g/mol)
Answer and explanation
Correct answer: B. 189 g
- Step 1: Mass = moles × molar mass. Step 2. 3 × 63 = 189 g. Answer: 189 g. Why not the others: 21 g is what you get if you divide the molar mass by the moles. 66 g is what you get if you add the numbers. 18.9 g is what you get if you misplace the decimal point.
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