What type of substances would make better permanent magnets, ferromagnetic or ferromagnetic. Justify your Solution.
A group 14 element is to be converted into n-type Semiconductor by doping it with a suitable impurity. To which group should this impurity belong?
Ionic solids, which have anionic vacancies due to metal excess defect, develop colour. Explain with the help of a suitable example.
Explain how vacancies are introduced in an ionic solid when a cation of higher valence is added as and impurity in it.