How many moles are in 490 g of H2SO4? (molar mass 98 g/mol)
Answer and explanation
Correct answer: B. 5 mol
- Step 1: The amount of substance is n = m / M.
- Step 2: n = m / M = 490 / 98 = 5 mol.
Answer
5 mol.
Why not the others: Moles are mass divided by molar mass; multiplying or adding gives other quantities.
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