What is the mass of 3 mol of H₂O? (molar mass 18 g/mol)
Answer and explanation
Correct answer: D. 54 g
- Step 1: Mass = moles × molar mass. Step 2. 3 × 18 = 54 g. Answer: 54 g. Why not the others: 6 g is what you get if you divide the molar mass by the moles. 21 g is what you get if you add the numbers. 5.4 g is what you get if you misplace the decimal point.
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