What happens when gypsum is heated to 373 K ? Give chemical equations

1.	What happens when gypsum is heated to 373 K ? Give chemical equations .
Answer» Solution :It is PREPARED by HEATING gypsum `(CaSO_4. 2H_2O)` at 373K ina kiln . `underset("Plaster of Paris")(CaSO_4. 2H_2O) to underset(373K)overset("Heat")to underset("Gypsum")(CaSO_4. 1/2 H_2O) + 1""1/2 H_2O ` `underset("Gypsum")(2CaSO_4 . 2H_2O) overset(373K) to underset("Plaster of Paris ")((CaSO_4)_2. H_2O) + 3H_2O ` It may be noted that the temperature should be controlled carefully. It should not be allowed to rise above 425 K, because the whole of water is lost and anhydrous calcium sulphate `(CaSO_4)` is produced. It is called dead burnt plaster. It has no such property as that of Plaster of Paris. When mixed with water, it FORMS a paste which sets into a hard mass. This is called SETTING of Plaster of Paris. The setting of Plaster of Paris is due to its hydration into gypsum. `(CaSO_4)_2. H_2O + 3H_2O to underset("(Gypsum)")(CaSO_4. 2H_2O)`

Discussion