The Solvay process is a method of producing sodium carbonate (Na₂CO₃) from brine and ammonia (NH₃). The process involves reacting brine with ammonia to form ammonium chloride (NH₄Cl), which is then reacted with limestone (CaCO₃) to produce carbon dioxide (CO₂), water (H₂O), calcium chloride (CaCl₂), and ammonia. The carbon dioxide is then reacted with the remaining ammonia to produce ammonium bicarbonate (NH₄HCO₃), which is then heated to produce sodium carbonate (Na₂CO₃), water, and carbon dioxide. Thus, the major product in the Solvay process is Na₂CO₃.