isotopes of hydrogen (deuterium and tritium)

Hydrogen, the simplest element, has three isotopes—variants with the same number of protons but different neutrons. The most common is protium, with no neutrons. Deuterium, or heavy hydrogen, has one neutron, making it heavier. Tritium has two neutrons, making it even heavier and radioactive. These isotopes behave similarly chemically but differ in atomic weight and nuclear stability. Deuterium is used in scientific research and heavy water reactors, while tritium is utilized in nuclear fusion and glow-in-the-dark applications.