A solution containing 7.5 g of urea (molar mass $=60 \mathrm{~g} \mathrm{~mol}^{-1}$ ) in 1 kg of water freezes at the same temperature as another solution containing 15 g of solute $X$, in the same amount of water. The molar mass of $X\left(\mathrm{~g} \mathrm{~mol}^{-1}\right)$ is

Two statements are given below

Statements I : Liquids $A$ and $B$ form a non-ideal solution with positive deviation. The interactions between $A$ and $B$ are weaker than $A-A$ and $B-B$ interactions.

Statements II : For an ideal solution $\Delta_{\text {mix }} H=0$; $\Delta_{\text {mix }} V=0$

The correct answer is

At 290 K , a vessel (I) contains equal moles of three liquids $(A, B, C)$. The boiling points of $A, B$ and $C$ are $350 \mathrm{~K}, 373 \mathrm{~K}$ and 308 K respectively. Vessel (I) is heated to 300 K and vapours were collected into vessel (II). Identify the correct statements. (Assume vessel (I) contains liquids and vapours and vessel (II)contains only vapours)

(I) Vessel - I is rich in liquid $B$

(II) Vessel - II is rich in vapour of $C$

(III) The vapour pressures of $A, B, C$ in vessel (I) at 290 K follows the order $C>A>B$