Example the following with suitable examples:
a. Ferromagnetism b. Paramagnetism
c. Ferrimagnetism d. Antiferromagnetism
e. 12 - 46 and 13 - 15 group compounds

Explanation

(i) Ferromagentism : When substances show permanent magnetism even in the absence of th emagnetic field this phenomenon is called as Ferromagnetism and such substances as called as Ferromagnetic substances e.g. Fe Ni Co and `CrO_(2)`.
(ii) Paramagnetism: When substances which are attracted by the external magnetic field are called paramagnetic substances and the phenomenon is called as paramagnetism. Atoms ion or molecules containing unpaired electron show this property, eq. `O_(2) Cu^(2+), Fe^(3+)` etc. These substances lost their magnestims in the absence of magnetic fields.
(iii) 13-15 Compounds: The solid state materials are produced by combination of elements of groups 13 and 15 the compound thus obtained are called 13-15 compounds e.q. InSb, AlP GaAs.
12 - 16 Compounds: The solid state compounds are obtained by combination of elements of groups 12 and 16 the compounds are called 12 - 16 compounds e.q. ZnS, CdS, CdSe and Hg Te.