Question

Molecule/s with atomicity 3 is/are:
A. ${O_3}$
B. ${O_2}$
C. NaCl
D. $C{O_2}$

Answer 1

Hint: The number of atoms in the molecule gives the atomicity of the molecule. Simply, It is the total number of atoms that composes the molecule.

Complete answer:
let us analyze all the options one by one.
> So the first option is ozone, that protects us from the harmful UV rays. It is made by reaction of diatomic oxygen with elemental oxygen. It evolves a lot of heat in the stratosphere and that’s why temperature increases with elevation. It has three oxygen atoms arranged in a bent structure . Hence its atomicity is 3.
> Oxygen is a diatomic molecule with two oxygen atoms. So the atomicity is 2.
> Similarly NaCl is also a diatomic molecule but it has different atoms.
> Carbon dioxide is a triatomic molecule as well with one carbon atom and two oxygen atoms. It is a linear arrangement of atoms where a carbon atom joins two oxygen atoms by double bond.

Hence the correct answers are A) and D).

Note: Different types of atomicity are:
Monoatomic: Consists of only one atom.
Diatomic: consists of only two atoms.
Triatomic: Consists of three atoms.
Polyatomic: Consists of more than three atoms.