What does the atomic number of an element represent?

A) the number of orbitals

B) the number of electrons

C) the number of neutrons

D) the number of protons

D) the number of protons

Answer: Option (D) is the correct answer.

Explanation:

Atomic number is the sum of total number of protons present in an atom.

For example, as atomic number of chlorine is 17 which also means that number of protons present in a chlorine atom are 17.

And, in a neutral atom the number of protons equal to the number of electrons.

Atomic mass is defined as the sum of total number of protons and neutrons present in an atom.

Therefore, we can conclude that the atomic number of an element represent the number of protons.