How many moles are there in 300 g of CaCO₃? (molar mass 100 g/mol)
Answer and explanation
Correct answer: A. 3 mol
- Step 1: Moles = mass ÷ molar mass. Step 2. 300 ÷ 100 = 3 mol. Answer: 3 mol. Why not the others: 30000 mol is what you get if you multiply the mass by the molar mass. 0.333 mol is what you get if you invert the ratio. 200 mol is what you get if you subtract the molar mass.
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