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 $C>A>B$
Observe the following reaction.
$$ A B \mathrm{O}_3(\mathrm{~s}) \xrightarrow{1000 \mathrm{~K}} A \mathrm{O}(\mathrm{~s})+B \mathrm{O}_2(\mathrm{~g}) $$
$\Delta_r H$ for this reaction is $x \mathrm{~kJ} \mathrm{~mol}^{-1}$. What is its $\Delta_r U$ (in $\mathrm{kJ} \mathrm{mol}^{-1}$ ) at the same temperature?
$$ \left(R=8.3 \mathrm{~J} \mathrm{~mol}^{-1} \mathrm{~K}^{-1}\right) $$