Welcome to the Community College of the Air Force (CCAF). Our college is a federally-chartered degree-granting institution that serves the United States Air Force's enlisted total force.
Isotopes of an element have nuclei with the same number of protons (the same atomic number) but different numbers of neutrons. Therefore, isotopes have different mass numbers, which give the total number of nucleons-the number of protons plus neutrons.
Definitions. Isotopes are atoms of the same element that have the same numbers of protons and electrons but different numbers of neutrons. The difference in the number of neutrons between the various isotopes of an element means that the various isotopes have similar charges but different masses.