The compound that is $NOT$ a common component of photochemical smog is

The relative contribution of $O_3$,$N_2O$,and $H_2O$ to global warming is in the ratio of ......

Photochemical smog consists of an excessive amount of $X$ in addition to aldehydes,ketones,$PAN$,etc. $X$ is:

Global warming is due to an increase of:

The consequence of global warming may be the following:

From the following,identify the reactions which are responsible for the depletion of the ozone layer.
$I. Cl\dot{O}_{(g)} + NO_{2_{(g)}} \rightarrow ClONO_{2_{(g)}}$
$II. CF_2Cl_{2_{(g)}} \xrightarrow{uv} \dot{Cl}_{(g)} + \dot{CF}_2Cl_{(g)}$
$III. \dot{Cl}_{(g)} + CH_{4_{(g)}} \rightarrow HCl_{(g)} + \dot{C}H_{3_{(g)}}$
$IV. \dot{Cl}_{(g)} + O_{3_{(g)}} \rightarrow Cl\dot{O}_{(g)} + O_{2_{(g)}}$
$V. Cl\dot{O}_{(g)} + O_{(g)} \rightarrow \dot{Cl}_{(g)} + O_{2_{(g)}}$