Question

Explain the industrial preparation of ammonia by Haber's process. Also, write two physical properties of ammonia.

Answer 1

Industrial production of ammonia gas is carried out by Habers process. In this method, dihydrogen and dinitrogen gases are mixed in 3:1 proportion by volume and then passed over iron catalyst at 200-300 bars of pressure. A temperature of about 773 K is maintained during this reaction. Substances like $A{l}_2{O}_3,K_{2}O$ are added to increase the efficiency of the catalyst. Hence, they are called propmoters. By cooling the reaction mixture at a temperature lower than 273 K, ammonia can be separated from the unreacted $N_2$ and $H_2$ gases. Thus, ammonia is obtained in the liquid form and $N_2$ and $H_2$ remain without reaction and can be used again to take part in the reaction.

$N_2\left(g\right)+3H_2\left(g\right)\underset{200-300bar/Fe}{\overset{773K}{\to }}2N{H}_3\left(g\right)+heat$

Physical properties of ammonia: Ammonia is a colourless gas. It possesses a very intensive smell, causing irritation in the nose and the eyes.