Question

What will be the vapour pressure of a solution containing $5$ moles of sucrose $\left(C_{12}{H}_{22}{O}_{11}\right)$ in $1kg$ of water, if the vapour pressure of pure water is $4.57mm$ of $Hg$ ? $[C=12,H=1,O=16]$

Answer 1

According to Raoults law:
$P_{solution}=P_{solvent}^0\times X_{solvent}$
$=4.57\times \frac{\frac{1000}{18}}{\frac{1000}{18}+5}$
$=4.57\times \frac{55.55}{55.55+5}$
$=4.192mm$ of Hg.