How many moles are in 36 g of H2O? (molar mass 18 g/mol)
Answer and explanation
Correct answer: B. 2 mol
- Step 1: The amount of substance is n = m / M.
- Step 2: n = m / M = 36 / 18 = 2 mol.
Answer
2 mol.
Why not the others: Moles are mass divided by molar mass; multiplying or adding gives other quantities.
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