Easy INTEGER +4 / -1 PYQ · JEE Mains 2021

1.46 g of a biopolymer dissolved in a 100 mL water at 300 K exerted an osmotic pressure of 2.42 $\times$ 10$-$3 bar.

The molar mass of the biopolymer is _____________ $\times$ 104 g mol$-$1. (Round off to the Nearest Integer)

[Use : R = 0.083 L bar mol$-$1 K$-$1]

Answer (integer) 15

Solution

$\pi$ = CRT;<br><br>$\pi$ = osmotic pressure<br><br>C = molarity<br><br>T = Temperature of solution<br><br>let the molar mass be M gm/mol<br><br>2.42 $\times$ 10<sup>$-$3</sup> bar = $${{\left( {{{1.46g} \over {Mgm/mol}}} \right)} \over {0.1l}} \times \left( {{{0.083l - bar} \over {mol - K}}} \right) \times (300K)$$<br><br>$\Rightarrow$ M = 15.02 $\times$ 10<sup>4</sup> g/mol

About this question

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

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