Which of the following equations is not involved in the Solvay process of manufacturing sodium bicarbonate.
CaCO3→heatCaO+CO2
NaCl+NH3+H2O+CO2→NH4Cl+NaHCO3
Ca(OH)2+2NH4Cl→2NH3+H2O+CaCl2
Na2CO3+CO2+H2O→Heat2NaHCO3
this process mainly involves formation of sodium bicarbonate by 2 but not by method shown in 4