The relative lowering in vapour pressure of an aqueous solution of urea which is $6\%$ by weight,is

At $25\,^oC$,the vapour pressure of $CCl_4$ is $143\,mm\,Hg$. If $0.5\,g$ of a non-volatile solute (molar mass $= 65\,g/mol$) is dissolved in $100\,mL$ of $CCl_4$,what will be the vapour pressure of the solution? (Density of $CCl_4 = 1.58\,g/cm^3$)

The vapour pressure of a solvent decreases by $10 \ mm$ of $Hg$ when a non-volatile solute is added to the solvent. The mole fraction of the solute in the solution is $0.2$. What should be the mole fraction of the solvent if the decrease in the vapour pressure is to be $20 \ mm$ of $Hg$?

The vapor pressure of an aqueous solution at $373 \, K$ is $0.925 \, atm$. What is the mole fraction of the solute?

At $25\,^{\circ}C$,the vapour pressure of pure liquid $A$ $(mol. wt. = 40)$ is $100\, torr$,while that of pure liquid $B$ is $40\, torr$ $(mol. wt. = 80)$. The vapour pressure at $25\,^{\circ}C$ of a solution containing $20\, g$ of each $A$ and $B$ is .......... $torr$.

Which of the following will have the lowest vapour pressure?