Exactly $1 \ g$ of urea dissolved in $75 \ g$ of water gives a solution that boils at $100.114 \ ^oC$ at $760 \ torr$. The molecular weight of urea is $60.1$. The boiling point elevation constant for water is

If an aqueous solution contains $9 \%$ and $1 \%$ $(w/w)$ of two non-volatile non-electrolytes $X$ (molecular weight $180$) and $Y$ (molecular weight $50$) respectively,the boiling point of the solution in ${ }^{\circ} C$ is approximately $(K_b = 0.52 \ K \ kg \ mol^{-1})$

The solution containing $18 \ g \ dm^{-3}$ of glucose (molar mass $180 \ g \ mol^{-1}$) in water and another containing $6 \ g \ dm^{-3}$ of solute $A$ in water boil at the same temperature. What is the molar mass of $A$?

If $10 \ g$ of a solute (molar mass $= 100 \ g/mol$) is dissolved in $100 \ g$ of water,then the molal elevation constant $K_b$ of the solvent will be equal to:

$A$ 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 $2.53 \ ^\circ C \ m^{-1}$.

What is molal elevation? Explain.