The following graph shows the vapour pressure (in $atm$) on the $y$-axis versus temperature $T$ (in $K$) on the $x$-axis for pure water and an aqueous urea solution. What is the boiling point (in $K$) of the urea solution? (Atmospheric pressure $= 1 \ atm$)

The elevation in boiling point of a solution containing $1.8 \ g$ of glucose in $100 \ g$ of solvent is $0.1^{\circ}C$. The value of $K_b$ for the solvent is ........ $\frac{K}{m}$.

$A$ solution is prepared by dissolving a $2.5 \ g$ sample of an unknown compound in $34 \ g$ of benzene,$C_6H_6$. The solution boils at $1.38 \ ^\circ C$ higher than pure benzene. Which expression gives the molar mass of the unknown compound? $K_b$ of $C_6H_6$ is $2.53 \ ^\circ C \ m^{-1}$.

Calculate the molality of a solution of a non-volatile solute if the boiling point elevation is $1.75 \ K$ and the $K_b$ for the solvent is $3 \ K \ kg \ mol^{-1}$. (in $m$)

$A$ solution containing $2.5 \times 10^{-3} \ kg$ of a solute dissolved in $75 \times 10^{-3} \ kg$ of water boils at $373.535 \ K$. The molar mass of the solute is $..... \ g \ mol^{-1}$. [nearest integer] (Given: $K_b(H_2O) = 0.52 \ K \ kg \ mol^{-1}$,boiling point of water $= 373.15 \ K$)

What is molal elevation? Explain.