isotopeista

Isotopes are variants of a particular chemical element which differ in neutron number, and consequently in nucleon number. All isotopes of a given element have the same number of protons in each atom. The number of protons determines the chemical element's atomic number, which is often denoted by Z. For example, all hydrogen atoms have one proton, but hydrogen can exist in three isotopic forms: protium, deuterium, and tritium. Protium has zero neutrons, deuterium has one neutron, and tritium has two neutrons.

The atomic mass of an isotope is determined by the sum of protons and neutrons in its nucleus. While isotopes of an element share the same chemical properties due to having the same number of electrons (which equals the number of protons in a neutral atom), they can have different physical properties, such as mass and radioactivity. Some isotopes are stable, meaning they do not spontaneously decay. Others are radioactive, and they undergo radioactive decay, emitting particles or energy to transform into a different isotope or element. The study and use of isotopes are widespread, including in nuclear power generation, medical imaging, carbon dating, and scientific research.