Only a few reactions are simple or straight forward, $i . e .$ purely first, second or third order reactions. But in most of the reactions, the interpretation of variety of data becomes difficult due to several other reactions taking place simultaneously alongwith the main reaction and thus smooth progress of the reaction is disturbed. Such reactions includes the following different types. The reactions in which a substance reacts or decomposes in more than one way, are called parallel or competing or side reaction. The reactions which take place exclusively on the walls of containing vessels are known as surface reactions. The reactions in which the products of chemical change react together to form the original reactants are called reversible reactions or opposing reactions or counter reactions. The reactions which proceeds from reactants to final products through one or more intermediate stages are called consecutive reactions.

During nitration of nitro benzene, nitro benzoic acid is also formed. Find out which nitro benzoic acid will be formed?