Ethylene glycol (molar mass =$62g mol^{-1})$ is a common automobile antifreeze.Calculate the freezing point of a solution containing 12.4 of this substance in 100g of water would it be advisable to keep this substance in the car radiator during summer?

Question

$\begin{array}{1 1}1.024K\\1.034K\\1.054K\\1.064K\end{array} $

Answer 1

$K_f$ for water =$1.86$kg/mol

$K_b$ for water =$0.512$kg/mol

$\Delta T_b=K_b\times \large\frac{W_B}{M_B}\times \frac{1000}{W_A}$

$\Rightarrow 0.512\times \large\frac{12.4}{62}\times \frac{1000}{100}$

$\Rightarrow 1.024K$

Since water boils at $100^{\large\circ}$C,so a solution containing ethylene glycol will boil at $101.04^{\large\circ}C$ so it is advisable to keep this substance in car radiator during summer.