Which one of the following is the chemical formula of gypsum?

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Q: 56 (NDA-II/2018)

Which one of the following is the chemical formula of gypsum?

question_subject: 

Science

question_exam: 

NDA-II

stats: 

0,5,4,5,2,1,1

keywords: 

{'chemical formula': [0, 0, 1, 3], 'gypsum': [0, 0, 1, 3], 'ca2sio4': [0, 0, 0, 1], 'caso4': [0, 0, 0, 1]}

The chemical formula of gypsum is CaSO4 .2H2O, which is option 1. Gypsum is a mineral that is commonly found in sedimentary rocks. It is a soft sulfate mineral composed of calcium sulfate dihydrate. Let`s dissect the other options to understand why they are not the correct chemical formula for gypsum.

Option 2, Ca2SiO4, does not represent gypsum but rather represents diopside, a mineral composed of calcium, silicon, and oxygen.

Option 3, 2CaSO4 .H2O, is not the correct chemical formula for gypsum either. This formula represents a different mineral called bassanite.

Option 4, CaSO4, only represents calcium sulfate without the water molecules. Gypsum, by definition, contains water molecules in its crystal structure, so this option is not correct.

In conclusion, option 1, CaSO4 .2H2O, is the correct chemical formula for gypsum.