Question

On heating gypsum at 373 k, it becomes calcium Sulphate hemihydrates which is called plaster of paris

Answer 1

heating of gypsum at 373k , it loses water molecules partially to become calcium sulphate hemihydrate. this is called plaster of paris (CaSO4.1/2 H2O). plaster of paris is a white powder and on mixing with water, it sets into hard solid mass due t the formation of gypsum