Answer:
0.6 mol/L.s.
Explanation:
3O₂ → 2O₃,
the rate of the reaction = - 1/3d[O₂]/dt = 1/2d[O₃]/dt
where, d[O₂]/dt is the rate of change of O₂ concentation = - 0.9 mol/L.s.
d[O₃]/dt is the rate of change of O₃ concentration.
∴ d[O₃]/dt = - 2/3(d[O₂]/dt) = - 2/3(- 0.9 mol/L.s) = 0.6 mol/L.s.