The chemical formula of gypsum is-

Correct option is D

The correct answer is (d) CaSO₄ · 2H₂O.
· Gypsum is a naturally occurring mineral composed of calcium sulfate dihydrate, and its chemical formula is CaSO₄ · 2H₂O.
· This indicates that each molecule of calcium sulfate is associated with two molecules of water.
· Gypsum is widely used in construction (for plaster and drywall), in agriculture as a soil conditioner, and in cement manufacturing.
Additional Information:
· CaSO₄ · 3H₂O : This does not represent gypsum; it would refer to a different hydrate form of calcium sulfate, which is not common.
· Na₂CO₃ · 8H₂O : This is sodium carbonate octahydrate, also known as washing soda, not gypsum.
· Na₂CO₃ · 10H₂O : This is sodium carbonate decahydrate, another form of washing soda, not related to gypsum.