Question

What is stoichiometry defect.Sxplain its classification?

Answer 1

It is generally known that all the compounds follow law of definite proportion. But there are certain solid compounds which, refuse to obey this universal law. Such solid compounds which actually do not possess the exact compositions according to the electronic considerations have been given the name Berthollide or non-stoichiometric compounds.

1.       Frenkel Defect

This defect generally arises when an ion occupies an interstitial position between lattice points.

2.       Schottky Defect

This is a defect which mainly arises if some of the lattice points are unoccupied.

3.       Substitutional Defects

Interchange of atoms between lattice sites produces this type of defect.