Question

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

• A. $NaCl$
• B. $C_{6}H_{12}O_{6}$
• C. $Al _{2}\left( SO _{4}\right)_{3}$
• D. $BaCl_{2}$

Answer 1

Answer: (C)

$\Delta T_{f} \propto i, A l_{2}\left(S O_{4}\right)_{3}( aq ) \Leftrightarrow 2 A l^{3+}+3 S O_{4}^{2-}$
[Total ions 5 ,thus, $i=5]$
$Al _{2}\left( SO _{4}\right)_{3}$ will exhibit largest freezing point depression due to the highest value of $i$.