Question

Sodium carbonate is also called
(A) Baking soda
(B) Washing soda
(C) Bleaching powder
(D) Bread soda

Answer 1

Hint: Sodium carbonate is a crystalline solid which is white in color. It exists as monohydrated salt, anhydrous salt, heptahydrate salt and decahydrate salt. It is basic in nature. When it is heated it has the tendency to lose water molecules and to form anhydrous salt called soda ash.

Complete answer: The chemical formula for sodium carbonate is \[N{{a}_{2}}C{{O}_{3}}.10{{H}_{2}}O\]. It is also known as washing soda . It is formed by the Solvay process. This process includes four steps in which purification of brine is the first. In this the concentrated brine is obtained by the evaporation process and the removal of calcium, magnesium particles occur by the precipitation process. Then this is mixed with ammonia in an ammonia tower, then it is cooled. Then the second step is formation of sodium hydrogen carbonate. This is done when carbon dioxide is passed through an ammoniated brine solution in a carbonate tower. Then the third step is the formation of sodium carbonate in which the sodium bicarbonate is heated at \[{{300}^{o}}\]C, which forms sodium carbonate. The last step is recovery of ammonia in which ammonia is recovered by treating the solution of \[N{{H}_{4}}Cl\]with calcium hydroxide. The formula for baking soda is \[NaHC{{O}_{3}}\]. The formula for bleaching powder is \[CaOC{{l}_{2}}\]. The formula for bread soda is \[NaHC{{O}_{3}}\].

The correct answer for this question is option(B).

Note: The uses for washing soda includes as a cleansing agent in industries and households. It is also used in manufacturing of paper and in softening of water. It is used in the process of detergent, soaps and in manufacturing of glass. As it exists as anhydrous salt, heptahydrate salt and decahydrate salt so the formula for them are \[N{{a}_{2}}C{{O}_{3}}\], \[N{{a}_{2}}C{{O}_{3}}.7{{H}_{2}}O\]and \[N{{a}_{2}}C{{O}_{3}}.10{{H}_{2}}O\]respectively.