The vapor pressure of water at a certain temperature is $3000 \ N \ m^{-2}$. When a non-electrolyte solute is added,it decreases by $300 \ N \ m^{-2}$. The molality of the solution is ............. $m$.

The vapour pressure of pure benzene and toluene are $160$ $mm \ Hg$ and $60$ $mm \ Hg$ respectively. The mole fraction of benzene in the vapour phase in contact with an equimolar solution of benzene and toluene is:

At $300 \ K$,the vapour pressures of two pure liquids,$A$ and $B$ are $100 \ mm \ Hg$ and $500 \ mm \ Hg$,respectively. If in a mixture of $A$ and $B$,the total vapour pressure is $300 \ mm \ Hg$,the mole fractions of $A$ in the liquid and in the vapour phase,respectively,are:

Which solution will show the maximum vapour pressure at $300 \ K$?

$X$ is a non-volatile solute and $Y$ is a volatile solvent. The following vapour pressures are observed by dissolving $X$ in $Y$ at different concentrations:
| $X / \text{mol L}^{-1}$ | $Y / \text{mm of Hg}$ |
| :--- | :--- |
| $0.10$ | $p_1$ |
| $0.25$ | $p_2$ |
| $0.01$ | $p_3$ |
The correct order of vapour pressures is:

The vapour pressure of pure water is $92.5 \ mm$ at $300 \ K$. The vapour pressure of $1 \ molal$ solution of $X$ in water is :-