At $80\,^oC$,the vapour pressure of pure liquid $A$ is $520\, mm\,Hg$ and that of pure liquid $B$ is $1000\, mm\,Hg$. If a mixture of $A$ and $B$ boils at $80\,^oC$ and $1\, atm$ pressure,the amount of $A$ in the mixture is ........... $mol\,\%$.

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].

The osmotic pressure of a solution of $NaCl$ is $0.10 \ atm$ and that of a glucose solution is $0.20 \ atm.$ The osmotic pressure of a solution formed by mixing $1 \ L$ of the sodium chloride solution with $2 \ L$ of the glucose solution is $x \times 10^{-3} \ atm.$ $x$ is.......... (nearest integer)

The freezing point of an aqueous solution is $-0.186 \ ^oC$. The boiling point of the same solution is ........ $^oC$. (Given: $K_f = 1.86 \ K \ kg \ mol^{-1}$ and $K_b = 0.512 \ K \ kg \ mol^{-1}$)

At $T \ K$,the vapour pressure of pure benzene $(C_6H_6)$ and toluene $(C_7H_8)$ are $75 \ mm \ Hg$ and $22 \ mm \ Hg$ respectively. $23.4 \ g$ of benzene and $64.4 \ g$ of toluene are mixed to form an ideal solution. If the vapours are in equilibrium with the liquid mixture,the mole fraction of toluene in the vapour phase is (Atomic weight: $C=12, H=1$).

Given below are two statements.
Statement-$I$: Liquids $A$ and $B$ form a non-ideal solution with negative deviation. The interactions between $A$ and $B$ are weaker than $A-A$ and $B-B$ interactions.
Statement-$II$: In reverse osmosis,the applied pressure must be higher than the osmotic pressure of solution.
The correct answer is