Look my friend,

 

When a carbon compound in ehich a double bond is present, is treated with ozone, an ozonide is formed. In this case also an ozonide is formed. You can check the structur from any book, i cannot make it here. sorry

 

Now, this ozonide has two carbons and both are chiral making the whole compound optically active. When Zn and H₂O are added, this ozonide breaks to form two compounds, both are carbonyl.

 

Note : An ozonide is an intermediate in ozonolysis. It is a cyclic structure where

          the two carbon chains on either side of the double bond in the original

         compound, are attached to two oxygens each. There are three oxygen

         atoms on a whole. This intermediate breaks into the carbonyl compounds

         on addition of Zn and water.

 

Hope you have got it. You can check in any book. It is given !!!