Question

1. Distinguish between A and B? 

2. Explain the defect in figure B. 

3. Give two examples of crystals showing this defect.

Answer 1

1. Fig. A – Ideal crystal. Fig. B – Frenkel defect.

2. Frenkel defect is due to the migration of cation from its original position to the void. This type of defect is favoured by the small size of cation. As a result of this defect, the neutrality, density and stoichiometry remain the same. But the conductivity increases.

3. AgCl, AgBr