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Wednesday, April 16, 2025

Chemical formula of plaster of paris:

Chemical formula of plaster of paris:
ACaSO₄
BCaSO₄.2H₂O
CCaSO₄.1/2 H₂O
DCaSO₄.H₂O

correct answer is: option c (CaSO₄.1/2 H₂O)
Explanation: Plaster of Paris is a hemihydrate of calcium sulfate. This means it contains half a molecule of water for every molecule of calcium sulfate. The chemical formula accurately reflects this ratio. When mixed with water, it rehydrates to form gypsum (CaSO₄.2H₂O), which is a hard, solid material.

  • Option A: CaSO₄ is the formula for anhydrous calcium sulfate (anhydrite), meaning it contains no water of crystallization.
  • Option B: CaSO₄.2H₂O is the chemical formula for gypsum, which is calcium sulfate dihydrate.
  • Option C: CaSO₄.1/2 H₂O is the correct chemical formula for Plaster of Paris, representing the hemihydrate form.
  • Option D: CaSO₄.H₂O would represent calcium sulfate monohydrate, which is not the chemical formula for plaster of paris.

Akhilesh
answered Apr 16 '25 at 23:05

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