Arrange the radicals (a) (C6H5)3C^., (b) C6H5CH2^., (c) (CH3)3C^. and (d) CH3^. in decreasing order of stability.

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JEE Main levelSingle correct optionDifficulty 2 of 3g3129

Arrange the radicals (a) $(C X_{6} H X_{5}) X_{3} C X^{∙}$ , (b) $C X_{6} H X_{5} CH X_{2} X^{∙}$ , (c) $(CH X_{3}) X_{3} C X^{∙}$ and (d) $CH X_{3} X^{∙}$ in decreasing order of stability.

A $b > a > d > c$
B $d > c > b > a$
C $c > a > b > d$
D $a > b > c > d$

Answer: D

Delocalisation of the unpaired electron over aromatic rings stabilises a radical far more than hyperconjugation does. The trityl radical (three rings) is the most stable, then benzyl (one ring), then the tertiary alkyl radical, and the methyl radical is the least stable.

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Arrange the radicals (a) (CX6​HX5​)X3​CX∙, (b) CX6​HX5​CHX2​X∙, (c) (CHX3​)X3​CX∙ and (d) CHX3​X∙ in decreasing order of stability.

Answer: D

More questions on Free radicals

Arrange the radicals (a) $(C X_{6} H X_{5}) X_{3} C X^{∙}$ , (b) $C X_{6} H X_{5} CH X_{2} X^{∙}$ , (c) $(CH X_{3}) X_{3} C X^{∙}$ and (d) $CH X_{3} X^{∙}$ in decreasing order of stability.