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 solution of $'A'$ and $'B'$ boils at $80\,^oC$ and $1\, atm$ pressure,the amount of $'A'$ in the mixture is ........... $mol$ percent $(1\, atm = 760\, mm\,Hg).$

An aqueous solution is $1.00 \ molal$ in $KI$. Which change will cause the vapour pressure of the solution to increase?

The vapour pressure in $mm$ of $Hg$ of an aqueous solution obtained by adding $18 \ g$ of glucose $(C_6H_{12}O_6)$ to $180 \ g$ of water at $100^{\circ}C$ is:

If vapour pressure of pure solvent and solution are $240 \ mm Hg$ and $216 \ mm Hg$ respectively,then the mole fraction of solvent in the solution is:

The variation of vapour pressure of different liquids with temperature is shown in the figure.
$(i)$ Calculate graphically the boiling points of liquids $A$ and $B$.
(ii) If we take liquid $C$ in a closed vessel and heat it continuously,at what temperature will it boil?
(iii) At high altitude,atmospheric pressure is low (say $60 \ mm \ Hg$). At what temperature does liquid $D$ boil?
(iv) $A$ pressure cooker is used for cooking food at hill stations. Explain in terms of vapour pressure why this is so.

The vapour pressures of pure liquids $A$ and $B$ are $400$ and $600\, mm\, Hg$,respectively at $298\, K$. On mixing the two liquids,the sum of their initial volumes is equal to the volume of the final mixture. The mole fraction of liquid $B$ is $0.5$ in the mixture. The vapour pressure of the final solution,the mole fractions of components $A$ and $B$ in vapour phase,respectively are