Question

Ozone is a gas heavier than air. Why does ozone layer not settle down near the earth?

Answer 1

Ozone is found to be thermodynamically unstable and undergoes decomposition into molecular oxygen and a dynamic equilibrium exists between the production and decomposition of ozone. The reactions involved can be shown as-

\[\ce{02 (g) ->[UV] O (g) + O (g)}\]

\[\ce{0 (g) + O2 (g) <->[UV] O3 (g)}\]