Formation of photochemical smog involves the following reaction in which $A , B$ and $C$ are respectively i $NO _2 \xrightarrow{ h\nu } A + B$ ii $B + O _2 \rightarrow C$ iii $A + C \rightarrow NO _2+ O _2$ Choose the correct answer from the options given below:
To solve this question, we need to analyze the reactions given and determine which species correspond to $A$, $B$, and $C$. Let's break down the reactions step by step:
First Reaction: \(NO_2 \xrightarrow{h\nu} A + B\)
This reaction indicates the photodissociation of nitrogen dioxide (\(NO_2\)) under the influence of light (denoted by \(h\nu\)). A possible dissociation product is nitric oxide (\(NO\)) and an oxygen atom (\(O\)). Therefore, we can assume \(A = NO\) and \(B = O\).
Second Reaction: \(B + O_2 \rightarrow C\)
The oxygen atom generated in the first reaction (denoted as \(B = O\)) reacts with molecular oxygen (\(O_2\)) to form ozone (\(O_3\)). Thus, \(C = O_3\).
Third Reaction: \(A + C \rightarrow NO_2 + O_2\)
In this reaction, \(A\) (which is \(NO\)) reacts with \(C\) (which is \(O_3\)) to regenerate nitrogen dioxide (\(NO_2\)) and release molecular oxygen (\(O_2\)).
Based on these reactions, we identify:
\(A = NO\)
\(B = O\)
\(C = O_3\)
From the options given, $NO , O \& O _3$ accurately matches the identified species for \(A, B,\) and \(C\). Thus, the correct answer is:
