Common salt (NaCl) is not used as a raw material for preparation of which one of the following compounds?

Common salt (NaCl) serves as a fundamental raw material for several industrial chemicals. It is used in the Solvay process to manufacture baking soda (sodium hydrogen carbonate) and washing soda (sodium carbonate) [1]. Additionally, the electrolysis of brine (aqueous NaCl) produces chlorine gas, which is then reacted with dry slaked lime to produce bleaching powder [1]. Consequently, bleaching powder, baking soda, and washing soda all rely on NaCl as a primary starting material [1]. In contrast, Plaster of Paris (calcium sulfate hemihydrate) is prepared by heating gypsum (calcium sulfate dihydrate) to a specific temperature. Its chemical composition is based on calcium and sulfur, and it does not involve sodium chloride in its production process. Therefore, NaCl is not a raw material for Plaster of Paris.

Sources

1. [1] Science , class X (NCERT 2025 ed.) > Chapter 2: Acids, Bases and Salts > Common salt — A raw material for chemicals > p. 30