In the equation given above, there is conservation of MASS, CHARGE AND ENERGY.
These three parameters are usually conserved during the course of chemical reactions. When any of these parameter experience a reduction during the course of chemical reaction, such loss is always gained by other elements involved in the same reaction, so that at the end of the day, they are not considered as lost.
One reaction that destroys o3 molecules in the stratosphere is when an ozone molecule combines with an oxygen atom to form two oxygen molecules, or through certain chemical reactions involving molecules containing hydrogen, nitrogen, chlorine, or bromine atoms. The atmosphere maintains a natural balance between ozone formation and destruction.
In order to get HgO you would need 2Hg+1O2=2HgO. Since oxygen is diatomic you need two when it stands alone causing you to need two mercuries to balance out the reactants and the product I hope this helps
Lets say foxes hunt rabbits. If their are too many foxes then they will compete for the rabbits. The rabbits get outnumbered by the amount of foxes so the foxes kill all the rabbits and the rabbits could eventually go extinct.
