In a 0.2 molal aqueous solution of a weak acid $HX$, the degree of ionization is 0.3. Taking $K_{f}$for water as 1.85, the freezing point of the solution will be nearest to

Question

Dr. Abubacker · Accepted Answer

(d)
$HX ightleftharpoons {\ \ \ H}^{+} + X^{-}$
1 mole 0 0 initial
$1 - 0.3\ \ 0.3\ \ 0.3$ after dissociation
Total moles $= 0.7 + 0.3 + 0.3 = 1.3$
$	herefore\ \ i = \frac{1.3}{1} = 1.3$
$\mathrm{\Delta}T_{f} = i 	imes k_{f} 	imes m = 1.3 	imes 1.85 	imes 0.2 = 0.481℃$
$	herefore T_{f} = T - \mathrm{\Delta}T_{f} = 0 - 0.481℃ = - 0.481℃$

Q. In a 0.2 molal aqueous solution of a weak acid $HX$, the degree of ionization is 0.3. Taking $K_{f}$for water as 1.85, the freezing point of the solution will be nearest to

Explanation

Reviewed by Dr. Abubacker

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