If two substances $A$ and $B$ have $P_{A}^{\circ} : P_{B}^{\circ} = 1 : 2$ and have mole fraction in solution in the ratio $1 : 2$,then mole fraction of $A$ in vapour phase is:-

$651 \ g$ of ethylene glycol $(HOCH_2CH_2OH)$ is dissolved in $1.5 \ kg$ of water at $363 \ K$. The vapour pressure of pure water at $363 \ K$ is $0.7 \ atm$. Assuming ideal solution behaviour,the vapour pressure of water over the solution (in $atm$) is closest to $...$

What weight of glucose must be dissolved in $100 \ g$ of water to lower the vapour pressure by $0.20 \ mm \ Hg$ (in $g$)? (Assume dilute solution is being formed) Given: Vapour pressure of pure water is $54.2 \ mm \ Hg$ at room temperature. Molar mass of glucose is $180 \ g \ mol^{-1}$

Which of the following will have the lowest vapour pressure?

The vapour pressure of water at room temperature is lowered by $5\%$ by dissolving a solute in it. Then the approximate molality of the solution is

Calculate the weight of non-volatile solute having molecular weight $40$,which is dissolved in $57 \ g$ octane to reduce its vapour pressure by $20\%$.