Sodium
Bicarbonate, commonly called baking soda, is a white
odourless, crystalline solid, completely soluble in
water but slightly soluble in ethanol. It is the mildest
of all sodium alkalis. It is prepared from purified
sodium carbonate or sodium hydroxide solution with passing
carbon dioxide which is bubbled into the solution of
pure carbonate, and the bicarbonate precipitates out
to be dried as the bicarbonate is less soluble than
the carbonate. Sodium bicarbonate is also made as an
intermediate product in the Solvay process which is
to make sodium carbonate from calcium carbonate by treating
sodium chloride with ammonia and carbon dioxide. The
major use of sodium bicarbonate is in baking powders.
Sodium Bicarbonate plays an important role in the products
of many diverse industries with functions of releasing
CO2 when heated above about 50 C or when reacted with
a weak acid makes sodium bicarbonate a key ingredient
in food leavening as well as in the manufacture of effervescent
salts and beverages. It can react as an acid or a base
in water treatment. In health and beauty applications,
mild abrasivity and ability to reduce odors chemically
by neutralizing the acid by-products of bacteria are
utilized. It is also used in treating wool and
silk, fire extinguishers, pharmacy, leather, oredressing,
metallurgy, in cleaning preparations and industrial
& chemical processe.