Of the Reactions Involved in the Photodecomposition of Ozone (Shown

Multiple Choice

Of the reactions involved in the photodecomposition of ozone (shown below) , which are exothermic?
1) O₂ (g) + hv → O (g) + O (g)
2) O (g) + O₂ (g) + M (g) → O₃(g) + M^* (g)
3) O₃ (g) + hv →O₂ (g) + O (g)
4) O (g) + O (g) + M (g) →O₂ (g) + M^* (g)

A) 2 only
B) 1, 2, and 4
C) 1 and 3
D) 2 and 4
E) all of them