Isotopes of the same element have what characteristic?

Isotopes of the same element are defined by having the same atomic number, which indicates the number of protons in the nucleus of an atom, confirming that they are indeed the same element. However, they differ in their mass numbers due to the variation in the number of neutrons present in the nucleus. This difference in mass number results in isotopes having distinct atomic weights while retaining the same chemical properties associated with their electron configuration.

This characteristic is crucial in understanding the various physical behaviors and applications of isotopes, such as in nuclear medicine, radiometric dating, and tracing chemical reactions. The concept of isotopes is important in the field of radiation protection as well, as different isotopes of the same element may have different radioactive properties and health effects.