Easy MCQ +4 / -1 PYQ · JEE Mains 2022

Two solutions A and B are prepared by dissolving 1 g of non-volatile solutes X and Y, respectively in 1 kg of water. The ratio of depression in freezing points for A and B is found to be 1 : 4. The ratio of molar masses of X and Y is

  1. A 1 : 4
  2. B 1 : 0.25 Correct answer
  3. C 1 : 0.20
  4. D 1 : 5

Solution

$\Delta T_{f}=i k_{f} \times m$ <br/><br/> $$ \frac{\Delta T_{\mathrm{f}(\mathrm{A})}}{\Delta \mathrm{T}_{\mathrm{f}(\mathrm{B})}}=\frac{1}{4} $$ <br/><br/> $$\frac{\mathrm{i} \times \mathrm{K}_{\mathrm{f}} \times \frac{1}{\mathrm{M}_{\mathrm{A}}} \times 1}{\mathrm{i} \times \mathrm{K}_{\mathrm{f}} \times \frac{1}{\mathrm{M}_{\mathrm{B}}} \times 1}=\frac{1}{4}$$ <br/><br/> $\frac{M_{B}}{M_{A}}=\frac{1}{4}$ <br/><br/> $M_{A}: M_{B}=4: 1$

About this question

Subject: Chemistry · Chapter: States of Matter · Topic: Gas Laws

This question is part of PrepWiser's free JEE Main question bank. 142 more solved questions on States of Matter are available — start with the harder ones if your accuracy is >70%.

Drill 25 more like these. Every day. Free.

PrepWiser turns these solved questions into a daily practice loop. Chapter-wise drills, full mocks, AI doubt chat. No auto-renew.

Start free →