Solutions Question 11

Question 11 - 30 January - Shift 2

Lead storage battery contains $38 %$ by weight solution of $H_2 SO_4$. The van’t Hoff factor is 2.67 at this concentration. The temperature in Kelvin at which the solution in the battery will freeze is

(Nearest integer).

Given $K_f=1.8 K kg mol^{-1}$

Show Answer

Answer: (243)

Solution:

$\Delta T_f=i \cdot K_f \cdot m$

$\Rightarrow \Delta T_f=2.67 \times 1.8 \times \frac{38}{98} \times \frac{1000}{62}$

$\Rightarrow \Delta T_f=30.05$