How many grams of a non-volatile solute with a molar mass of $90$ must be dissolved in $97.5 \ g$ of water to cause a $2.5 \%$ decrease in vapour pressure?

Choose the correct statement with respect to the vapour pressure of a liquid among the following:

The vapour pressure of pure $CCl_4$ (molar mass $= 154 \ g \ mol^{-1}$) and $SnCl_4$ (molar mass $= 170 \ g \ mol^{-1}$) at $25^{\circ} C$ are $115.0 \ torr$ and $238.0 \ torr$ respectively. Assuming ideal behaviour, calculate the total approximate vapour pressure in $torr$ of a solution containing $10 \ g$ of $CCl_4$ and $15 \ g$ of $SnCl_4$.

If $P_0$ and $P_s$ are the vapour pressures of the solvent and its solution respectively,and $N_1$ and $N_2$ are the mole fractions of the solvent and solute respectively,then which of the following is correct?

The vapour pressure of two liquids $P$ and $Q$ are $80$ and $60 \, torr$,respectively. The total vapour pressure of the solution obtained by mixing $3 \, mole$ of $P$ and $2 \, mole$ of $Q$ would be .......... $torr$.

Relative lowering of vapour pressure of a dilute solution of glucose dissolved in $1 \ kg$ of water is $0.002$. The molality of the solution is (in $m$)