How many moles are there in 8 g of CH₄? (molar mass 16 g/mol)
Answer and explanation
Correct answer: A. 0.5 mol
- Step 1: Moles = mass ÷ molar mass. Step 2. 8 ÷ 16 = 0.5 mol. Answer: 0.5 mol. Why not the others: 128 mol is what you get if you multiply the mass by the molar mass. 2 mol is what you get if you invert the ratio. -8 mol is what you get if you subtract the molar mass.
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