👉 An isotope is a type of element that contains an atomic number and a mass number. The atomic number represents the number of protons in the nucleus, while the mass number represents the total number of nucleons (protons plus neutrons). Isotopes are variations on the same element with different numbers of protons or different masses.
For example, isotope A has an atomic number of 12 and a mass number of 34. Isotope B also has an atomic number
isotopes