Q75 / 180 · NEET 2014 · Chemistry

Of the following $0.10 m$ aqueous solutions, which one will exhibit the largest freezing point depression?

Solution

Colligative properties are directly proportional to the number of solute particles.

On dissociation of ${Al}_{2} {({SO}_{4})}_{3} \to 2 {Al}^{+ 3} + 3 {SO}_{4}^{2 -}$

$i = \frac{5}{1} = 5$

$∆ T_{f} = i K_{f} m$

$i$ is highest for $A l_{2} {(S O_{4})}_{3}$

Hence, the correct answer is option: 'C'.