(a) Using the BDEs in Table 4-2 (p. 143), compute the value of Ho for each step...

(a) Using the BDEs in Table 4-2 (p. 143), compute the value of ΔHo for each step in the iodination of methane.
(b) Compute the overall value of ΔHo for iodination.
(c) Suggest two reasons why iodine does not react well with methane

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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