$1$ molal $K_{4}[Fe(CN)_{6}]$ solution has a degree of dissociation of $0.4$. Its boiling point is equal to that of another solution which contains $18.1$ weight percent of a non-electrolytic solute $A$. The molar mass of $A$ is $.......\, u$. (Round off to the Nearest Integer). [Density of water $= 1.0\, g\, cm^{-3}$]

Two elements $A$ and $B$ form compounds having formula $AB_{2}$ and $AB_{4}$. When dissolved in $20 \ g$ of benzene $(C_{6}H_{6})$,$1 \ g$ of $AB_{2}$ lowers the freezing point by $2.3 \ K$ whereas $1.0 \ g$ of $AB_{4}$ lowers it by $1.3 \ K$. The molar depression constant for benzene is $5.1 \ K \ kg \ mol^{-1}$. Calculate atomic masses of $A$ and $B$.

At $T(K)$,the vapour pressure of pure benzene (molar mass $= 78 \ g \ mol^{-1}$) is $0.85 \ bar$. When $2.0 \ g$ of a non-volatile,non-electrolyte solute is added to $39 \ g$ of benzene,the vapour pressure of the solution at $T(K)$ is $0.83 \ bar$. The elevation in boiling point (in $K$) of the same solution is: ($K_b$ of benzene is $2.6 \ K \ kg \ mol^{-1}$)

Give examples of ideal solutions and azeotropes.

$W \ g$ of a non-volatile electrolyte solid solute of molar mass $M \ g \ mol^{-1}$ when dissolved in $100 \ mL$ water,decreases vapor pressure of water from $640 \ mm \ Hg$ to $600 \ mm \ Hg$. If aqueous solution of the electrolyte boils at $375 \ K$ and $K_b$ for water is $0.52 \ K \ kg \ mol^{-1}$,then the mole fraction of the electrolyte solute $(X_2)$ in the solution can be expressed as (Given density of water $= 1 \ g/mL$ and boiling point of water $= 373 \ K$):

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