Sodium carbonate: Sodium carbonate is an inorganic chemical compound whose molecular symbol is Na²CO³ . It is also known as washing soda , soda ash and soda crystal. Sodium can be distinguished from plants grown in sodium-rich soils, such as the Middle Eastern vegetable kelp, Scotland, and marine weeds in Spain. This type of plant is called soda ash because it is obtained from ash. It is used in the production of various commercial products.