An aqueous solution of a non-electrolyte boils at $100.52 \, ^\circ C$. The freezing point of the solution will be ............ $^\circ C$.

Drinking water contains some salt impurities dissolved in it. When this solution is heated in an open container,vapours are formed and separated slowly. In this process,the freezing point and osmotic pressure of the remaining solution will continuously

$20\%$ of acetic acid is dissociated when its $5\ g$ is added to $500\ mL$ of water. The depression in freezing point of such water is $..... \times 10^{-3} \ { }^{\circ}C$. Atomic mass of $C$,$H$,and $O$ are $12$,$1$,and $16 \ \text{a.m.u.}$ respectively.
[Given: Molal depression constant and density of water are $1.86 \ K \ kg \ mol^{-1}$ and $1 \ g \ cm^{-3}$ respectively.]

Which of the following mixtures is known as Proof Spirit (by volume)?

$A$ solution at $20\,^oC$ is composed of $1.5\,mol$ of benzene and $3.5\,mol$ of toluene. If the vapour pressure of pure benzene and pure toluene at this temperature are $74.7\,torr$ and $22.3\,torr,$ respectively,then the total vapour pressure of the solution and the benzene mole fraction in equilibrium with it will be,respectively

$A$ solution of urea (molar mass $60 \, g \, mol^{-1}$) boils at $100.18 \, ^oC$ at atmospheric pressure. If $K_f$ and $K_b$ for water are $1.86$ and $0.512 \, K \, kg \, mol^{-1}$ respectively,the above solution will freeze at ........... $^oC$.