Sodium carbonate

Sodium carbonate, Na2CO3, (also known as washing soda, soda ash and soda
crystals) is the inorganic compound with the formula Na2CO3 and its
various hydrates. All forms are white, water-soluble salts. All forms have a
strongly alkaline taste and give moderately alkaline solutions in water.
Historically it was extracted from the ashes of plants growing in sodium-
rich soils. Because the ashes of these sodium-rich plants were noticeably
different from ashes of wood (once used to produce potash), sodium
carbonate became known as "soda ash".[12] It is produced in large
quantities from sodium chloride and limestone by the Solvay process.
Soda ash is one of the most  important chemical raw materials and is widely
used in chemical, glass, metallurgy, paper making, printing & dyeing,
synthetic detergent, petrochemical, foodstuff, medicine & sanitation
industries, etc. With a large consumption, it occupies a crucial place in
national economy.

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