Addition of 4.0 g of a non-volatile solute to 54.0 g water results in a lowering of vapour pressure — Solutions and Colligative Properties Chemistry Question

💡 Solution & Explanation

Using the exact relative lowering formula: $\frac{P^\circ - P}{P} = \frac{n}{N} \implies \frac{1}{99} = \frac{4/M}{54/18} = \frac{4/M}{3} \implies M = \frac{4 \times 99}{3} = 132$ g/mol. Therefore, correct answer is A.