Question

Molecular mass of nitrogen is 28. Its atomic mass is 14. Find the atomicity of nitrogen.
a.) 1
b.) 2
c.) 4
d.) 8

Answer 1

Hint: From the word atomicity we can understand that this problem is talking about the number of atoms. And molecules are the combination of more than one atom.

Complete answer:
Atomicity denotes the number of atoms present in a single molecule of an element, substance or compound. It can also be considered as the nature of molecules. And atomicity can’t be broken into further small portions. Atomicity can be determined as a ratio of molecular mass and atomic mass. According to the atomicity of a substance, the atomicity can be mono, di, tri and poly. For example oxygen has atomicity 2, inert gases (He, Ne etc.) are monoatomic, in ozone atomicity 3, and ${{P}_{4}}$ is polyatomic.
Given, molecular mass of nitrogen = 28
Atomic mass of nitrogen = 14
Then, atomicity of nitrogen = molecular mass of nitrogen / atomic mass of nitrogen
= 28 / 14
= 2
So, the atomicity of nitrogen is “2”. Which means that one nitrogen molecule contains two nitrogen atoms.

So, the answer is 2.

Note: In a molecule there can be similar types of atoms or can also be different molecules for example: ${{O}_{2}}$ and ${{H}_{2}}O$. Atomicity is the number of atoms in a molecule not in one mole. So, don’t get confused with molecule and mole.