Question

Iodine is dissolved in $C_6{H}_6$ solution. The mole fraction of $I_2$ in solution is 0.25. Find out the molarity of he solution.

Answer 1

Mole fraction= $0.25$

$\therefore$ In $100$ moles $25$ moles of $I_2$ & $75$ moles are $C_6{H}_6$

$\therefore$ Mass of benzene= $75\times 78=5850g$ (Molar mass of benzene= $78$)

$\therefore$ For $5850g$ of solvent we have $25$ moles of $I_2$.

$\therefore$ For $1000g$ of solvent we have,

$=\frac{1000\times 25}{5850}=4.27M$

Hence molarity of the solution= $4.27M$