$12 \ g$ of urea is dissolved in $1 \ L$ of water and $68.4 \ g$ of sucrose is dissolved in $1 \ L$ of water. The lowering of vapour pressure of the first case is

Calculate the vapour pressure of pure volatile liquid $B$ $(P_B^o)$ at a given temperature if the mole fraction of liquid $B$ $(x_B)$ is $0.4$ and the vapour pressure of pure volatile liquid $A$ $(P_A^o)$ is $400 \ mm \ Hg$. The total vapour pressure of the solution is $P_{total} = 600 \ mm \ Hg$. (in $mm \ Hg$)

"Relative lowering in vapour pressure of a solution containing a non-volatile solute is directly proportional to the mole fraction of the solute". The above statement is:

What is the vapour pressure of a solution containing $0.1 \ mol$ of non-volatile solute dissolved in $16.2 \ g$ of water (in $mm \ Hg$)? $(P_1^{\circ} = 32 \ mm \ Hg)$

Which one of the following is the incorrect form of Raoult's law?

The vapour pressures of pure liquids $A$ and $B$ are $400$ and $600\, mm\, Hg$,respectively at $298\, K$. On mixing the two liquids,the sum of their initial volumes is equal to the volume of the final mixture. The mole fraction of liquid $B$ is $0.5$ in the mixture. The vapour pressure of the final solution,the mole fractions of components $A$ and $B$ in vapour phase,respectively are