Answer:
the coefficient of oxygen is 3
Step-by-step explanation:
When oxygen molecule is pass through an electrical spark ozone O3 molecules are formed. This same reaction takes place in the Earth's atmosphere during the formation of the ozone layer.
The balanced reaction looks like
3O2 -----------> 2O3 [ in presence of electric spark]
From the balance equation we can say that the coefficient of oxygen is 3 and that of ozone is 2
However, lab preparation of ozone, uses a Laser spark plug ignition system.