Answer 1

Solvay process is used to prepare sodium carbonate.

When carbon dioxide gas is bubbled through a brine solution saturated with ammonia, sodium hydrogen carbonate is formed. This sodium hydrogen carbonate is then converted to sodium carbonate.

Step 1: Brine solution is saturated with ammonia.

`2NH_3 + H_2O + CO_2 -> (NH_4)_2 CO_3`

This ammoniated brine is filtered to remove any impurity.

Step 2: Carbon dioxide is reacted with this ammoniated brine to result in the formation of insoluble sodium hydrogen carbonate.

NH₃+H₂O+CO₂→NH₄HCO₃

NaCl+NH₄HCO₃→NaHCO₃+NH₄Cl

Step 3: The solution containing crystals of NaHCO₃ is filtered to obtain NaHCO₃.

Step 4: NaHCO₃ is heated strongly to convert it into NaHCO₃.

`2NaHOC_3 -> Na_2CO_3 + CO_2 + H_2O`

Step 5: To recover ammonia, the filtrate (after removing NaHCO₃) is mixed with Ca(OH)₂ and heated.

Ca(OH)₂+2NH₄Cl→2NH₃+2H₂O+CaCl₂

The overall reaction taking place in Solvay process is  `2NaCl + CaCO_3 -> Na_2CO_3 + CaCl_2`