Question

By passing silent electric discharge into $50 mL$ of pure and dry oxygen gas, the volume of ozonized oxygen became $47 mL$. On treatment with turpentine oil to absorb ozone the volume became $41 mL$. Find the molecular formula of ozone.

Answer 1

Volume of pure and dry $O_{2}=50 mL$

Vol. of ozonised oxygen $=47 mL$

Vol. after absorption of ozone $=41 mL$

From these data, vol, of $O _{2}$ which changed to ozone

$=(50-41) mL =9 mL$

and vol. of ozone formed in the reaction $=(47-41) mL =6 mL$.

We then conclude that

$9 mL$ of $O _{2}$ change to $6 mL$ ozone

or. $3 mL$ of $O _{2}$ change to $2 mL$ ozone

or, 3 molecules of $O_{2}$ give 2 molecules of ozone

or, 6 atoms of $O_{2}$ give 2 molecules of ozone

That is, one molecule of ozone contains 3 atoms of oxygen.

Hence, the formula of ozone $= O _{3}$.