Sodium Bicarbonate from Soda Ash and Carbon Dioxide

Sodium bicarbonate, sold as baking soda, is made from sodium carbonate (soda ash): Na₂CO₃ + CO₂ + H₂O → 2 NaHCO₃. Soda ash is dissolved in water and treated with carbon dioxide, and sodium bicarbonate comes out of the solution as a solid. In 1846 John Dwight and Austin Church opened the first factory in the United States to make baking soda this way. Dry the product gently: from 80–100 °C sodium bicarbonate slowly breaks down again into sodium carbonate, water and carbon dioxide.