Question

The vapour pressure of a dilute aqueous solution of glucose is $750mm$ of mercury at $373K$. The mole fraction is:

• A. $\frac{1}{10}$
• B. $\frac{1}{7.6}$
• C. $\frac{1}{35}$
• D. $\frac{1}{76}$

Answer 1

The correct option is D $\frac{1}{76}$

We have $P_0=760mm,P=750mm$
$\frac{P_0-P}{P_0}=x_2$ ($x_2$ = mole fraction of solute)
$\frac{760-750}{760}=x_2$
$\frac{10}{760}=x_2$
$x_2=\frac{1}{76}$