A solution of urea was found to be isotonic with a solution of salt $\mathrm{XY}$ of molecular weight $74.6$. If $0.15$ moles of urea are dissolved in a certain volume $\mathrm{V} \mathrm{mL}$ of the isotonic solution, the amount of salt in the solution will be :

According to this phase diagram, which phases can exist at pressures lower than the triple point pressure?

The elevation in the boiling point of a solution containing $13.44 \mathrm{g}$ of ${\mathrm{CuCl}}_2$ in $1 \mathrm{kg}$ of water is

$({\mathrm{K}}_{\mathrm{b}}=0.52 \mathrm{K} \mathrm{kg} {\mathrm{mol}}^{–1})$

Which of the following observation indicates colligative property?

$\mathrm{I}.$ A $0.5 \mathrm{M} \mathrm{NaBr}$ solution has a higher vapour pressure than $0.5 \mathrm{M} {\mathrm{BaCl}}_2$.

$\mathrm{II}.$ A $0.5 \mathrm{M} \mathrm{NaOH}$ solution freezes at a lower temperature than pure water.

$\mathrm{III}.$ Pure water freezes at a higher temperature than pure ethanol.