The preparation of 2-chloro-4-nitroaniline from aniline and chlorine gas involves two main steps: nitration and chlorination. 1. Nitration of aniline:C6H7N + HNO3 -> C6H6N2O2 + H2OIn this step, aniline C6H7N reacts with nitric acid HNO3 to form 4-nitroaniline C6H6N2O2 and water H2O .2. Chlorination of 4-nitroaniline:C6H6N2O2 + Cl2 -> C6H5ClN2O2 + HClIn this step, 4-nitroaniline C6H6N2O2 reacts with chlorine gas Cl2 to form 2-chloro-4-nitroaniline C6H5ClN2O2 and hydrogen chloride HCl .Overall balanced chemical equation:C6H7N + HNO3 + Cl2 -> C6H5ClN2O2 + H2O + HCl