a) What happens if too much of acid is produced in the stomach? What is the remedy for this situation?
b) What is water of crystallization?
c) Write any two uses of plaster of paris .

Explanation

(a) If too much of acid is produced in the stomach it causes hyperacidity (Irritation and pain). To get rid of this pain we have to use bases called antacids. It neutralises excess of acid and gives relief from pain caused by hyperacidity.
(b) the fixed number of water molecules present in one formula unit of a crystaline salt is called water of crystallisation. Plaster of paris is prepared by heating gypsum to a temperature of `100^@C.`
The following reaction takes place :
` CaSO_4 . 2H_2O overset(100^@C)(to) CaSO_4 . 1/2 H_2O + 1/2H_2O `
i) it is used to prepare chalks .
ii) It is used to make casts and moulds.