0.25 mol of solute is dissolved to make 2 dm³ of solution. What is the molarity?
Answer and explanation
Correct answer: A. 0.125 mol/dm³
- Step 1: Molarity = moles ÷ volume in dm³. Step 2. 0.25 ÷ 2 = 0.125 mol/dm³. Answer: 0.125 mol/dm³. Why not the others: 0.5 mol/dm³ is what you get if you multiply moles by volume. 8 mol/dm³ is what you get if you invert the ratio. 2.25 mol/dm³ is what you get if you add the numbers.
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