Mole concept.?

Question

20 cm^3 of ozone are partly decomposed by heat to form oxygen. the equation is as follows:
2 O^2 ---> 3 O^3.
After the decompostion, the total volume of gas is 25 cm^3. Calculate the volumes of ozone and oxygen respectively in the final reaction mixture.

Answer 1

The eqn should be

2O^3->3O^2

Let vol of O3 decomposed be x

So, final vol = 20 - x + 3x/2 = 25

So, x/2 = 5

x = 10

Thus vol of O3 = 10 cm^3 and vol of O2 = 15 cm^3