Question

The solution which has lowest freezing point temperature is:

• A. $0.1MMg{Cl}_2$
• B. $0.1MHCl{O}_4$
• C. $0.1MN{H}_{4}OH$
• D. $0.1MKOH$
• E. $0.1MLiN{O}_3$

Answer 1

The correct option is A $0.1MMg{Cl}_2$

All the given solutions have the same molarity. The solution which has the lowest freezing point temperature is $0.1MMg{Cl}_2$.

The solution which has the lowest freezing point temperature is one which has the highest depression in freezing point ( $\Delta T_f$).

The depression in freezing point is a colligative property and depends on the number of solute particles. Greater is the number of solute particles, greater is the depression in the freezing point.

1 molecule of $Mg{Cl}_2$ dissociates to produce 3 ions, whereas 1 molecule of other solutes dissociates to produce 2 ions.