Ionic solids, which have anionic vacancies due to metal excess defect, develop colour. Explain with the help of a suitable example.

Explain the following terms with suitable examples: Frenkel defect

Explain the following terms with suitable examples: Schottky defect

A blackish brown coloured solid 'A' when fused with alkali metal hydroxides in presence of air, produces a dark green coloured compound 'B' which on electrolytic oxidation in alkaline medium gives a dark purple coloured compound 'C' Identify A, B and C and write the reactions involved.

Explain how vacancies are introduced in an ionic solid when a cation of higher valence is added as an impurity in it.

Explain the following terms with suitable examples in each case. Anionic detergents.

Write feature which will distinguish a metallic solid from an ionic solid?