Question

Is the plaster of Paris useful in setting a solid mass?

(a) Yes

(b) No

(c) Maybe

(d) Cannot say

I had been asked this question during an internship interview.

The question is from s-Block Elements in chapter s-Block Elements of Chemistry – Class 11

Answer 1

The correct choice is (a) Yes

To explain: When plaster of Paris or calcium sulphate hemihydrate which is given by the chemical formula CaSO4.1/2H2O is mixed with water, it forms of plastic mass which sets into a solid mass with slight expansion due to dehydration and its reverse conversion into gypsum.