In nuclear physics, a decay product, also known as a daughter product, is a nuclide resulting from the radioactive decay of a parent or precursor nuclide. Nuclear physics is the branch of physics concerned with the nucleus of the atom. ... Isotopes are atoms of a chemical element whose nuclei have the same atomic number, Z, but different atomic weights, A. The word isotope, meaning at the same place, comes from the fact that isotopes are located at the same place on the periodic table. ... Radioactive decay is the set of various processes by which unstable atomic nuclei (nuclides) emit subatomic particles (radiation). ...

Decay products are extremely important in understanding radioactive decay and the management of radioactive waste. A Russian fissile material storage facility Underground Radioactive Material Sign Radioactive waste is waste material containing radioactive chemical elements that does not have a practical purpose. ...

In practice nearly all decay products are themselves radioactive. The result of this is that most radionuclides do not have simply a decay product, but rather a decay chain, leading eventually to a stable nuclide. For elements above lead in atomic number, this is nearly always an isotope of lead. Lead is generally the stable point at which decay chains stop. Nearly all the decay products of radioactive decay are themselves radioactive. ... General Name, Symbol, Number lead, Pb, 82 Chemical series poor metals Group, Period, Block 14, 6, p Appearance bluish white Atomic mass 207. ... The atomic number (Z) is a term used in chemistry and physics to represent the number of protons found in the nucleus of an atom. ... Isotopes are forms of an element whose nuclei have the same atomic number–-the number of protons in the nucleus--but different atomic masses because they contain different numbers of neutrons. ...

In many cases members of the decay chain are far more radioactive than the original nuclide. Thus, although uranium is not dangerously radioactive when pure, some pieces of naturally-occurring pitchblende are quite dangerous owing to their radium content. Similarly, thorium gas mantles are very slightly radioactive when new, but become far more radioactive after only a few months of storage. Uraninite is a uranium-rich mineral with a composition that is largely UO2 (uranium oxide), but which also contains UO3 and oxides of lead, thorium, and rare earths. ... General Name, Symbol, Number radium, Ra, 88 Chemical series alkaline earth metals Group, Period, Block 2, 7, s Appearance silvery white metallic Atomic mass (226) g/mol Electron configuration [Rn] 7s2 Electrons per shell 2, 8, 18, 32, 18, 8, 2 Physical properties Phase solid Density (near r. ... General Name, Symbol, Number thorium, Th, 90 Chemical series transition metals Group, Period, Block ?, 7, f Appearance silvery white Atomic mass 232. ... For other uses of mantle see: mantle (disambiguation) An incandescent gas mantle, gas mantle, or Welsbach mantle is a device for generating bright white light when heated by a flame. ...

Although it cannot be predicted whether any given atom of a radioactive substance will decay at any given time, the decay products of a radioactive substance are extremely predictable. Because of this, decay products are important to scientists in many fields who need to know the quantity or type of the parent product. Such studies are done to measure pollution levels (in and around nuclear facilities) and for other matters.