Soda Ash Soda Ash (also known as washing soda or Sodium Carbonate), it is a sodium salt of carbonic acid. It has a chemical formula of Na2CO3. Soda ash is a versatile product that can be produced inexpensively and used for a number of different applications. By far, the majority of sodium carbonate is used to make glass. The next largest use is to make a variety of chemicals, followed by soaps and detergents, distributors, the removal of sulfur from smokestack emissions, paper and paper pulp production, water treatment, and other assorted uses.