Dissolution of $1.5 \ g$ of a non-volatile solute (mol. wt. $= 60$) in $250 \ g$ of a solvent reduces its freezing point by $0.01 \ ^{\circ}C$. Find the molal depression constant of the solvent.

$K_{f}$ (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 $^{\circ} C$)

What will be the freezing point of a $1\%$ aqueous solution of $Ca(NO_3)_2$?

Two elements $A$ and $B$ form compounds with molecular formulas $AB_2$ and $AB_4$. When $1 \ g$ of $AB_2$ is dissolved in $20 \ g$ of $C_6H_6$,the freezing point decreases by $2.3 \ K$. When $1 \ g$ of $AB_4$ is dissolved in $20 \ g$ of $C_6H_6$,the freezing point decreases by $1.3 \ K$. The molal depression constant for benzene is $5.1 \ K \ kg \ mol^{-1}$. Calculate the atomic weights of $A$ and $B$.

What is the freezing point depression constant of a solvent,$50 \ g$ of which contains $1 \ g$ of a non-volatile solute (molar mass $256 \ g \ mol^{-1}$) and the decrease in freezing point is $0.40 \ K$?

How much amount of $NaCl$ should be added to $600 \ g$ of water $(\rho=1.00 \ g / mL)$ to decrease the freezing point of water to $-0.2^{\circ} C ?$ ............. $gm$
(The freezing point depression constant for water $=2 \ K \ kg \ mol^{-1}$ )