It is represented as O3. It is found in upper atmosphere.
- It is prepared when ultraviolet rays. They react with oxygen of upper atmosphere and splits oxygen molecule in oxygen atoms. Then this oxygen atom combines with oxygen molecule to form ozone:
- 3O2 ---> 2O3
- Oxygen Ozone
- The reaction is endothermic approx. 142.7kJ of heat is needed.
- For preparing pure ozone we use ozoniser, in which the electric spark is passed through oxygen gas and we get ozone.