$80$ mole percent of $MgCl_2$ is dissociated in aqueous solution. The vapour pressure of $1.0$ molal aqueous solution of $MgCl_2$ at $38^{\circ} C$ is $.........$ $mm$ $Hg$. (Nearest integer)
Given : Vapour pressure of water at $38^{\circ} C$ is $50$ $mm$ $Hg$.

Calculate the freezing point (in ${}^{\circ}C$) of a solution obtained by dissolving $0.1 \ g$ of potassium ferricyanide (molecular weight $= 329$) in $100 \ g$ of water. Given that $K_f$ for water is $1.86 \ K \ kg \ mol^{-1}$.

Which of the following will have the lowest vapor pressure?

Which one of the following $0.10 \ M$ aqueous solutions will exhibit the largest freezing point depression?

The elevation in boiling point of a solution of $10 \ g$ of a binary electrolyte (of molecular mass $100$) in $100 \ g$ of water is $\Delta T_b$. Then,the value of $K_b$ for water is

$19.5 \text{ g}$ of fluoroacetic acid (molar mass = $78 \text{ g mol}^{-1}$) is dissolved in $500 \text{ g}$ of water at $298 \text{ K}$. The depression in the freezing point of water was $1^\circ\text{C}$. What is $K_a$ of fluoroacetic acid? (For water, $K_f = 1.86 \text{ K kg mol}^{-1}$). Assume molarity and molality to have same values.