Question

The atomic mass of oxygen is 16 and the molecular mass of ozone is 48. What is the atomicity of ozone if it is an allotrope of oxygen?
a.) 1
b.) 2
c.) 3
d.) 4

Answer 1

Hint: “Atomicity is defined as the total number of atoms that constitute a molecule”. For example, each oxygen molecule (\[{{O}_{2}}\]) is composed of two oxygen atoms. So the atomicity of an oxygen molecule is 2.
The existence of a chemical element in two or more forms is called allotropy.

Complete step by step answer:
We know that the molecular formula of oxygen is \[{{O}_{2}}\].
The molecular formula of Ozone is \[{{O}_{3}}\].
Given that the atomic mass of oxygen is 16 and molecular mass of ozone is 48.
We have to calculate the atomicity of oxygen in ozone
Atomicity of oxygen in ozone
\[\begin{align}
  & =\dfrac{\text{molecular mass of ozone}}{\text{Atomic mass of oxygen}} \\
 & =\dfrac{48}{16} \\
 & =3 \\
\end{align}\]

Therefore, the atomicity of oxygen in ozone is Three.

So, the correct option is C.

Additional information:
Ozone (\[{{O}_{3}}\]) is a pale blue gas with a distinctively pungent smell.
It can be manmade and available naturally too.
It occurs in earth’s upper atmosphere.
The shape of the ozone molecule is V-like.
The ozone layer is an invisible shield and protects the humans from harmful ultraviolet (UV) radiation from the sun.

Note: Don’t be confused with ozone and oxygen.
Ozone (\[{{O}_{3}}\]) contains three oxygen atoms and oxygen contains two oxygen atoms. But both are allotropes of oxygen.
Oxygen reacts with nascent oxygen and forms ozone (\[{{O}_{3}}\]).