The isotopes of a chemical element are a group of atoms of that have the same atomic numbers but different mass numbers. This implies that all isotopes of an element have the same number of protons in their atomic nuclei and the same number of electrons in the electron cloud surrounding the nucleus. However, they differ in the total number of neutrons present in their respective atomic nuclei.
- The difference between different isotopes of the same element is based on their masses.
- Mass is used as a parameter to differentiate as the number of neutrons present in the isotopes varies based on their mass. This is a way to differentiate between isotopes.
Three isotopes of hydrogen
- Protium, or hydrogen-1. This isotope of hydrogen contains 1 proton, 1 electron, and no neutrons.
- Deuterium, or hydrogen-2. This isotope of hydrogen contains 1 proton, 1 electron, and 1 neutron.
- Tritium, or hydrogen-3. This isotope of hydrogen contains 1 proton, 1 electron, and 2 neutrons. It can also be noted that this isotope of hydrogen is radioactive.