Question

Which of the following is a radical ?
(This question has multiple correct options )
A. $F$
B. $Cl$
C. $S{O_4}$
D. $C{O_3}$

Answer 1

A free radical is defined as an atom or a group of atoms which have an odd number of electrons or unpaired electrons . They are generally produced by homolytic cleavage of a covalent bond .

Complete step by step answer:
Radicals can be classified as primary , secondary and tertiary according to whether the atom carrying the unpaired electron is primary , secondary or tertiary respectively . They can have positive or negative charge or can be neutral .
The radicals can be generated in many ways , like redox reactions , heat , electrical discharges and
electrolysis . Radicals act as intermediate species in many chemical reactions . They are important in
combustion , polymerization , biochemistry and many other chemical reactions .
Since fluorine and chlorine both have an odd number of electrons they are radicals . Also sulphate and carbonate act as a single unit . They also contain unpaired electrons hence they also act as free radicals .
Hence all the four given entities , that is , fluorine , chlorine , sulphate and carbonate are free radicals .
Hence option A , B , C and D are correct .

Note:
Generally free radicals like carbocations are planar chemical species . But sometimes , just like carbanions , free radicals can also assume pyramidal shape since the energy difference between planar and pyramidal shapes is not much .