Question

An example of anti-Ferro-magnetic material is:
(a) Salt of transition elements
(b) Rare earth elements
(c) Transition metals
(d) Ferrites

Answer 1

Hint: The substances that possess zero net magnetic moments but are expected to have a permanent paramagnetism or ferromagnetism based on the magnetic moment. The anti-ferromagnetic materials have an equal number of opposite domains.

Complete step by step answer:
There are five types of solids based on magnetic properties:
(i) Diamagnetic: When the magnetic field is applied on the solid then the substance is weakly repelled by the external magnetic field. This is due to the fully-filled orbitals.
(ii) Paramagnetism: When the magnetic field is applied on the solid then the substance is attracted by the external magnetic field but the magnetic field has been removed.
(iii) Ferromagnetism: When the magnetic field is applied then the substance is attracted by the external magnetic field but when the magnetic field is removed these substances still have magnetism.
(iv) Anti-ferromagnetism: When the magnetic field is applied the substances are supposed to have a permanent magnetic field, but they possess zero net magnetic fields. They have equal opposite domains.
(v) Ferrimagnetism: When the magnetic field is applied the substances are supposed to have a large magnetic field but they possess a small magnetic field.
So, salts of transition elements are the example of Anti-ferromagnetism, rare earth elements are the examples of ferromagnetism, transition metals are paramagnetic, and ferrites are the examples of ferrimagnetism.

Therefore the correct answer is an option (a) Salts of transition metals.

Note: Some substances are very strongly attracted to the magnetic field this is due to the reason that these substances in a solid-state, the metal ions of these substances group together to form domains. These domains act like a tiny magnet.