Q. Solution A contains 7 g/L of $MgCl_{2}$ and solution B contains 7 g/L of NaCl. At room temperature, the osmotic pressure of

A) 50
B) 180
C) 102
D) 25
Explanation

(c)
According to Raoult’s law
$\frac{p - p_{s}}{p} = \frac{n}{n + N} = \frac{0.05}{2.5 + 0.05}$
$= \frac{0.05}{2.55} = \frac{1}{51}$
weight of solute $= \frac{w}{W} \times M \times \frac{p}{p - p_{s}}$
= $\frac{10 \times 18}{90} \times 51$
=102 g

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.

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