Which one of the following is the chemical formula of Plaster of Paris ?

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Q: 94 (NDA-II/2021)

Which one of the following is the chemical formula of Plaster of Paris ?

question_subject: 

Science

question_exam: 

NDA-II

stats: 

0,5,11,8,5,3,0

keywords: 

{'chemical formula': [0, 0, 1, 3], 'plaster': [0, 0, 1, 0], 'cas04': [0, 0, 0, 2], 'paris': [9, 1, 6, 11], 'h20': [0, 0, 0, 4]}

The chemical formula of Plaster of Paris is represented by the option 1: CaS04. — H20.

Plaster of Paris is a type of calcium sulfate hemihydrate, which means that it contains one molecule of calcium sulfate (CaS04) and half a molecule of water (H20). The ratio of calcium sulfate to water in Plaster of Paris is 1:0.5.

Option 2 (CaS04. 2 H20) suggests that there are two molecules of water for every molecule of calcium sulfate.

Option 3 (CaS04. 5 H20) suggests that there are five molecules of water for every molecule of calcium sulfate.

Option 4 (CaS04. 4 H20) suggests that there are four molecules of water for every molecule of calcium sulfate.

However, the correct formula for Plaster of Paris has one molecule of calcium sulfate and only half a molecule of water.

In summary, the correct chemical formula for Plaster of Paris is CaS04. — H20, as stated in option 1.