Use bond-dissociation enthalpies (Table 4-2) to calculate values of for the following reactions.
(a) CH3 - CH3 + I2 †’ CH3 CH2I + HI
(b) CH3 CH2 Cl + HI †’ CH3 CH2 I + HCl
(c) (CH3)3C -OH + HCl †’ (CH3)3C - CL + H2O
(d) CH3 CH2CH3 + H2 †’ CH3CH3 + CH4
(e) CH3 CH2 OH + HBr †’CH3CH2 -Br + H2O

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TABLE 4-2 Bond-Dissociation Enthalpies for Homolytic Cleavages A:BA-+-B kcal/mol Bond H-X bonds and X X bonds Bonds to sacondary carbons D-D F-F a-C Br-Br 1-1 H-F H--CI H-Br (CHCH-H (CH CH-F (CH,CH-CI (CH, CH- Br CHHCH-I CHACH OH 38 335 192 151 381 136 431 Bonds to tertiary carbons 381 (CH),CH CHCF (CH)C-C (CH),C-Br (CH),C-I CH,,C-OH 71 119 HO-H 331 213 Medıyl bond CH,-H CH3-F 381 91 351 PhCH H (benzylic) C CHH H (allylic) CH CH H (viny) Ph H(aromatic) HC-m C-H (acetylenic) CH, Br 70 CH OH 381 91 113 Bonds to primary carto 410 CH,CH F CH,CH C CH,CH Br CH,CHI CH,CH,-OH CH,CH CH2 H CH,CH CH F CH,CH CH CI CH,CH CH Br CH,CH CH2I CH,CH CH2 OH 107 C-C bonds CH CH CH,CH CH, CH,CH, CH,CH (CH)CH- CH (CH),C CH 285 381 410 91 351 81 381 91