Q. Vapour pressure of dilute aqueous solution of glucose is 750 mm of mercury at 373 K. The mole fraction of solute is
A) $\frac{1}{76}$
B) $\frac{1}{7.6}$
C) $\frac{1}{38}$
D) $\frac{1}{10}$
Explanation
(a)
According to Raoult’s law
Mole fraction of solute =$\frac{p - p_{s}}{p}$
$\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ = \frac{760 - 750}{760} = \frac{10}{760} = \frac{1}{76}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.