# The physical properties of isotopes differ due to:

The physical properties of the isotopes differ due to different mass numbers.

## Isotopes

Isotopes are atoms that have different numbers of neutrons but the same number of protons. From the above definition of atomic mass and the atomic number, we can conclude that isotopes are those elements having the same atomic number and different mass number.

Examples – Vanadium, carbon, calcium, potassium are stable isotopes.