The vapor pressure of a pure liquid solvent $(X)$ decreases from $0.80 \ atm$ to $0.60 \ atm$ upon the addition of a non-volatile solute $(Y)$. What is the mole fraction of $(Y)$ in the solution?

According to Raoult's law for a non-volatile solute,which of the following is correct?

$A$ solution is prepared by mixing $8.5 \ g$ of $CH_2Cl_2$ and $11.95 \ g$ of $CHCl_3$. If the vapour pressures of pure $CH_2Cl_2$ and $CHCl_3$ at $298 \ K$ are $415 \ mm \ Hg$ and $200 \ mm \ Hg$ respectively,the mole fraction of $CHCl_3$ in the vapour phase is: (Molar mass of $Cl = 35.5 \ g \ mol^{-1}$)

When $5 \ g$ of a non-electrolyte solute is dissolved in $100 \ g$ of water,the vapor pressure decreases from $3000 \ N \ m^{-2}$ to $2985 \ N \ m^{-2}$. The molar mass of the solute is ............... $g/mol$.

At $50^{\circ} C$, the vapour pressure of pure benzene is $268 \ torr$. The number of moles of non-volatile solute per mole of benzene required to prepare a solution having a vapour pressure of $167 \ torr$ at the same temperature is (molar mass of benzene $= 78 \ g \ mol^{-1}$)

At $T \ K$,the vapour pressure of an $x$ molal aqueous solution containing a non-volatile solute is $12.078 \ kPa$. The vapour pressure of pure water at $T \ K$ is $12.3 \ kPa$. What is the value of $x$?