Use bond enthalpy values to calculate the enthalpy change for the following reaction. Then, label if the reaction is endothermic or exothermic
CH4 (g) + Br2 (g) —> CH3Br (g) + HBr (g)
-H
H-C-H O - O O = C = O H - O - H
-H
H - Br
Bond Breaking Bond making
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C-H (413 kJ/mol) + Br-Br (193 kJ/mol) - C-Br (346 kJ/mol) - H-Br (366 kJ/mol)
Enthalpy change = -(413 + 193) + (346 + 366) = -60 kJ/mol
The reaction is exothermic.