Question

what is the chemical formula of plaster of paris how is it prepared

Answer 1

caso41/2H2o is the formula of pop...it means calcium hemihydrate

Answer 2

CaSO4. 1/2(half) H20(plaster of Paris) + 1 1/2(one&half) H2O(water) -----> CaSO4. 2H20
(Gypsum)
So, when gypsum is heated at 373K temperature a compound is formed with water called PLASTER OF PARIS (write the above eqn in reverse order)
Its chemical name is cacliumsulphuroxide hemahydrate
; ) hope its will help u...