Question

what is gypsum?why is it called plaster of paris?

Answer 1

gysum is chemically,(caso4.2h2o).Gypsum is the common name of hydrated calcium sulphate, which has the chemical formula CaSO4.2H2O. 


It is also used in manufacturing Plaster of Paris.plaster of paris is so called because gypsum was early used near Paris to make plaster and cement. 

Answer 2

Gypsum is a naturally occurring mineral. It is chemically calcium sulphate dihydrate (CaSO₄ . 2H₂O).
Gypsum is also called Plaster of Paris because it is obtained by chemically by heating the gypsum at controlled temperature. 
Plaster of Paris formula : ( (CaSO₄)₂ . H₂O )