Which of the following statements is correct for the boiling point of a solvent containing a dissolved solid substance?

If the boiling points of two solvents $X$ and $Y$ (having same molecular weights) are in the ratio $2 : 1$ and their enthalpies of vaporization are in the ratio $1 : 2$,then the boiling point elevation constant of $X$ is $\underline{ m }$ times the boiling point elevation constant of $Y$. The value of $m$ is $.....$. (Nearest integer)

When a substance is dissolved in a solvent,the vapour pressure of the solvent is decreased. This results in:

Which of the following aqueous solutions will exhibit the highest boiling point?

To observe an elevation of boiling point of $0.05^{\circ} C$,the amount of a solute (mol. wt. $= 100$) to be added to $100 \ g$ of water $(K_{b} = 0.5)$ is (in $g$)

The boiling point of $0.2 \ m$ aqueous urea solution is $....... \ ^oC$. ($K_b$ of water $= 0.52 \ K \ kg \ mol^{-1}$)