Question

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

• A. $K_{2}\text{S}\text{O}_{4}$
• B. KCl
• C. $\text{A}\left(\text{l}\right)_{2}\left(\right.\text{S}\left(\text{O}\right)_{4}\left(\left.\right)_{3}$
• D. $C_{6}H_{\text{12}}O_{6}$

Answer 1

Answer: (C)

As molar concentration is same so only deciding factor is van't Hoff factor
Depression in freezing point $ \propto $ van't Hoff's factor for $\text{A}\left(\text{l}\right)_{2}\left(\right.\text{S}\left(\text{O}\right)_{4}\left(\left.\right)_{3} \rightarrow i=5$
$K_{2}\text{S}\text{O}_{4} \rightarrow i=3$
$\text{KCl} \rightarrow i=2$
$C_{6}H_{\text{12}}O_{6} \rightarrow i=1$