Describe solvay process (or) how is washing soda ( or) sodium carbonate prepared in industries?

Explanation

Salvay process - in this process ammonia is converted to ammonium carbonate, which e then converted to ammonium bicarbonate by passing excess carbon dioxide in sodium chloride solution saturated with ammonia.
The ammonium bicarbonate formed reacts with sodium chloride to give sodium bicarbonate.As sodium bicarbonate has poor solubility, it gets precipitated.
The sodium bicarbonate is isolated and is heated to give sodium carbonate.
(iv) The equations involved in this process is as below: (i)`2NH_(3) + H_(2)O + CO_(2) tounderset("Ammonium carbonate") ((NH_(4))_(2)CO_(3))`
`(NH_(4))_(2)CO_(3)+H_(2)O+CO_(2)tounderset("Ammonium bicarbonate")(2NH_(4)HCO_(3))`
(iii)`NH_(4)HCO_(3) + NaCl to underset("Ammonium chloride")(NH_(4)Cl + NaHCO_(3))`
`2NaHCO_(3)overset(/_\)tounderset("Sodium carbonate")(Na_(2)CO_(3)+)CO_(2)+H_(2)O`