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NEET levelSingle correct optionDifficulty 1 of 3o2057

The relative ease of abstraction of hydrogen atoms from an alkane by a halogen radical follows the order

Aall are abstracted at equal rates
Bsecondary $>$ tertiary $>$ primary
Ctertiary $>$ secondary $>$ primary
Dprimary $>$ secondary $>$ tertiary

Answer: C

The C-H bond dissociation energy decreases from primary to tertiary, and the radical formed gains stability by hyperconjugation in the order

3^{\circ} > 2^{\circ} > 1^{\circ}

. Hence tertiary H is abstracted most easily.

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