Chapter 4.12, Problem 4.16P

The bromination of methane proceeds through the following steps:

${\text{Br}}_2\stackrel{hv}{\to }2\text{Br}\cdot \frac{\Delta H^{\circ }(\text{per mole})}{+190\text{kJ (45 kcal)}}\frac{E_a(\text{per mole})}{190\text{ kJ (45 kcal)}}$

CH₄ + Br· → · CH₃ + HBr + 73 kJ (17 kcal) 79 kJ (19 kcal)

· CH₃ + Br₂ → CH₃Br + Br^· − 112 kJ (− 27 kcal) 4 kJ (1 kcal)