The molecular formula of the product formed when benzene is reacted with excess of chlorine molecules under ultra-violet light is

The order of decreasing reactivity towards an electrophilic reagent, for the following compounds, is

(i) benzene

(iii) chlorobenzene

(ii) toluene

(iv) phenol

The major product of the following reaction is

$$ \text { Glucose } \frac{\text { (i) } \mathrm{HI}, \Delta}{\text { (ii) } \mathrm{Mo}_2 \mathrm{O}_3, 773 \mathrm{~K}, 10 \cdot 20 \mathrm{am}} $$

The major products $P$ and $Q$ in the following reactions, respectively, are