Assertion : A free radical is paramagnetic
species.
Reason : A free radical is formed in
homolytic fission of covalent bond.

(a) Both Assertion and Reason are true and Reason
is the correct explanation of Assertion.
(b) Both Assertion and Reason are true but Reason is
not the correct explanation of Assertion.
(c) Assertion is true but Reason is false.
(d) Both Assertion and Reason are false.

Please explain the solution in detail.

A free-radical is defined as an atom or group of atoms which contains an unpaired electron.These are formed by homolytic cleavage of a covalent bond in presence of U.V light.Free-radicals are highly reactive species because of presence of one unpaired electron so they have tendency to share it with some other atom or group to complete its octet.For ex-alkyl free-radicals,chlorine free-radicals etc.
If we study the structure of alkyl free-radical we will found that C-carrying unpaired e- is sp2 hybridised.Three-sp2 hybridised orbitals are used in forming three sigma bonds with other atoms and the unpaired e- is present in the unhybridised p-orbital which is perpendicular to the plane of sigma-bonds.This unpaired e- makes the free-radical an paramagnetic species.So the option (b) is the correct answer.