K_{f} (water) = 1.86 K kg mol^{-1}. The te | vedclass

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(C) The depression in freezing point is given by $\Delta T_{f} = K_{f} 	imes m$. Here,$10 \%$ mass of ethylene glycol ($C_2H_6O_2$,molar mass $= 62 \

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$-3.3$

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(C) The depression in freezing point is given by $\Delta T_{f} = K_{f} 	imes m$. Here,$10 \%$ mass of ethylene glycol ($C_2H_6O_2$,molar mass $= 62 \ g \ mol^{-1}$) means $10 \ g$ of solute in $90 \ g$ of water. Molality $(m)$ $= \frac{	ext{mass of solute}}{	ext{molar mass of solute} 	imes 	ext{mass of solvent in kg}} = \frac{10}{62} 	imes \frac{1000}{90} \approx 1.79 \ mol \ kg^{-1}$. $\Delta T_{f} = 1.86 	imes 1.79 \approx 3.33^{\circ} C$. Since the freezing point of pure water is $0^{\circ} C$,the temperature at which ice begins to separate is $0 - 3.33 = -3.33^{\circ} C$,which is approximately $-3.3^{\circ} C$.

$K_{f}$ (water) $= 1.86 \ K \ kg \ mol^{-1}$. The temperature at which ice begins to separate from a mixture of $10$ mass $\%$ ethylene glycol is (in $^{\circ} C$)

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