👉 The term "postpyretic" refers to a type of gas produced during nuclear fusion reactions. This gas is known as deuterium, which is used as fuel in various forms of nuclear power plants. In more detail, deuterium is a radioactive isotope that contains one proton and two neutrons. During nuclear fusion reactions, the neutrons from the nucleus are released into space as deuterium, while the protons from the nucleus combine with electrons to form helium-3 (
