-->

The P-Block Elements

Question
CBSEENCH12006791

How is ammonia manufactured industrially? 

Solution
Ammonia is manufactured industrially by Haber's process.
N2(g) + 3H2(g)  2NH3(g)  f H° = -46.1 kJ mol-1

A mixture of dry nitrogen and hydrogen gases in the ratio of 1:3 by volume is compressed to about 200 to 300 atm and passed over iron catalyst at a temperature of about 723 k to 773 k. The iron catalyst is mixed with aluminium oxide (Al
2O3) and potassium oxide (K2O) which act as promotors.
Ammonia being formed is continuously removed by liquefying it. 
The optimum conditions for the production of ammonia are a pressure of about 200 atm, a temperature of ~700 k and use of a catalyst such as iron oxide with small amounts of K2O and Al2,O3 to increase the rate of attainment of equilibrium.