$P_A = (235y - 125xy) \, \text{mm of Hg}$. $P_A$ is the partial pressure of $A$,$x$ is the mole fraction of $B$ in the liquid phase in the mixture of two liquids $A$ and $B$,and $y$ is the mole fraction of $A$ in the vapour phase. Then $P^o_B$ in $\text{mm of Hg}$ is:

$100 \ mL$ of $1.5\%(w/v)$ solution of urea has an osmotic pressure of $6.0 \ atm$ and $100 \ mL$ of $3.42\%(w/v)$ solution of cane sugar has an osmotic pressure of $2.4 \ atm$. If the two solutions are mixed,the osmotic pressure of the resulting solution in $atm$ is (Assume that there is no reaction between urea and cane sugar).

Match the following.

$A$. Ebullioscopic constant	$I$. Depression of freezing point
$B$. Cryoscopic constant	$II$. Total pressure is the sum of partial pressures of the components
$C$. Henry's law	$III$. Elevation of boiling point
$D$. Dalton's law	$IV$. Solubility of a gas in liquid

The correct match is

An aqueous solution of urea:

At $100\, ^oC$ the vapour pressure of a solution of $6.5\, g$ of a solute in $100\, g$ water is $732\, mm.$ If $K_b = 0.52,$ the boiling point of this solution will be .........$^oC$

The elevation in boiling point for $1 \ m$ solution of non-volatile solute $A$ is $3 \ K$. The depression in freezing point for $2 \ m$ solution of $A$ in the same solvent is $6 \ K$. The ratio of $K_{b}$ and $K_{f}$ i.e.,$K_{b} / K_{f}$ is $1 : X$. The value of $X$ is [nearest integer].