31 g of ethylene glycol $\left(C_{2} H_{6} O_{2}\right)$ is mixed with 400 g of water. $K_{f}$ of wa

Question

31 g of ethylene glycol $\left(C_{2} H_{6} O_{2}\right)$ is mixed with 400 g of water. $K_{f}$ of water is $1.86 K kg mol^{-1}$. The solution freezes at

Professor PC Thomas Classes · Answer

Molality of the solution, $m=\frac{w_{2} 	imes 1000}{M_{2} w_{1}}=\frac{31 	imes 1000}{62 	imes 400}=1.25 \Delta T_{f}=K_{f} m=1.86 	imes 1.25=2.325$ Freezing point of solution $=T_{f}=273.15-2.325=270.825 K$