Easy INTEGER +4 / -1 PYQ · JEE Mains 2023

At $27^{\circ} \mathrm{C}$, a solution containing $2.5 \mathrm{~g}$ of solute in $250.0 \mathrm{~mL}$ of solution exerts an osmotic pressure of $400 \mathrm{~Pa}$. The molar mass of the solute is ___________ $\mathrm{g} \mathrm{~mol}^{-1}$ (Nearest integer)

(Given : $\mathrm{R}=0.083 \mathrm{~L} \mathrm{~bar} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}$)

Answer (integer) 62250

Solution

$\pi = CRT$ <br/><br/>$$ \begin{aligned} 400 & =\frac{2.5}{\mathrm{m_w}} \times 4 \times\left(.083 \times 10^5\right) \times 300 \\\\ \mathrm{m_w} & =\frac{10 \times 0.083 \times 3}{4} \times 10^5 \\\\ & =62250 \end{aligned} $$

About this question

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

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