Question

What is the natural source of \[{\text{N}}{{\text{a}}_{\text{2}}}{\text{C}}{{\text{O}}_{\text{3}}}\]
A ) Nitre
B ) Chile saltpeter
C ) Dolomite
D ) Trona

Answer 1

Hint: Trona and chile saltpeter contains sodium metal. Nitrile contains potassium metal. Dolomite contains magnesium and calcium metals.

Complete step by step answer:
> \[{\text{N}}{{\text{a}}_{\text{2}}}{\text{C}}{{\text{O}}_{\text{3}}}\] is sodium carbonate. It is also known as washing soda or soda ash. It is an inorganic chemical.
> Trona ore is the natural source of sodium carbonate. Trona is trisodium hydrogendicarbonate dihydrate it is also called sodium sesquicarbonate dihydrate. Its chemical formula is \[{\text{N}}{{\text{a}}_2}{\text{C}}{{\text{O}}_{\text{3}}}\left(Na{{\text{HC}}{{\text{O}}_{\text{3}}}} \right){\text{.2}}{{\text{H}}_{\text{2}}}{\text{O}}\].
Thus trona is double salt containing sodium carbonate and sodium hydrogen carbonate
At lakes, series of evaporation processes result in the formation of trona. From trona, soda ash is extracted.
> Nitre is potassium nitrate \[{\text{KN}}{{\text{O}}_{\text{3}}}\].
> Chile saltpeter is sodium nitrate \[{\text{NaN}}{{\text{O}}_{\text{3}}}\].
> Dolomite is a mixed carbonate of calcium and magnesium. Its chemical formula is \[{\text{CaMg}}{\left( {{\text{C}}{{\text{O}}_{\text{3}}}} \right)_2}\].

Hence, the option D ) Trona is the correct option.

Additional Information: There are four different processes to produce sodium carbonate. These include Electrolysis, Solvay process, Dual-process and Leblanc process. Sodium carbonate has application as a water softener. It precipitates calcium and magnesium cations present in hard water. Aqueous solution of sodium carbonate has pH around 10.52. In aqueous solution, the hydrolysis of sodium carbonate gives hydroxide ions , which causes the solution to be a mildly alkaline solution. Anhydrous sodium carbonate does not undergo thermal decomposition. Sodium carbonate is used in making soaps, detergents, paper, etc.

Note: Compared to sodium hydroxide, sodium carbonate is non-corrosive in nature and relatively safer to handle. Sodium carbonate is used in the preparation of soaps and detergents. It is also used to soften hard water.