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Phosphorus is a member of the pnictogens, together with nitrogen, arsenic, antimony, bismuth, and moscovium, and consequently shares properties with them. Phosphorus is an element essential to sustaining life largely through phosphates, compounds containing the phosphate ion, PO 4 3−.
Phosphors can be classified into two categories: fluorescent substances which emit the energy immediately and stop glowing when the exciting radiation is turned off, and phosphorescent substances which emit the energy after a delay, so they keep glowing after the radiation is turned off, decaying in brightness over a period of milliseconds to days.
Further blurring the lines, a substance may emit light by one, two, or all three mechanisms depending on the material and excitation conditions. [ further explanation needed ] [ 11 ] When the stored energy becomes locked in by the spin of the atomic electrons , a triplet state can occur, slowing the emission of light, sometimes by several ...
The frequencies of light that an atom can emit are dependent on states the electrons can be in. When excited, an electron moves to a higher energy level or orbital. When the electron falls back to its ground level the light is emitted. Emission spectrum of hydrogen. The above picture shows the visible light emission spectrum for hydrogen. If ...
White phosphorus, yellow phosphorus or simply tetraphosphorus (P 4) exists as molecules of four phosphorus atoms in a tetrahedral structure, joined by six phosphorus—phosphorus single bonds. [1] The free P 4 molecule in the gas phase has a P-P bond length of r g = 2.1994(3) Å as was determined by gas electron diffraction . [ 2 ]
People exposed to white phosphorus can suffer severe and sometimes deadly bone-deep burns. It can cause organs to shut down, and burns on just 10% of the body can be fatal, HRW said.
The phosphorus cycle is the biogeochemical cycle that involves the movement of phosphorus through the lithosphere, hydrosphere, and biosphere.Unlike many other biogeochemical cycles, the atmosphere does not play a significant role in the movement of phosphorus, because phosphorus and phosphorus-based materials do not enter the gaseous phase readily, [1] as the main source of gaseous phosphorus ...
Radioluminescent paint is a self-luminous paint that consists of a small amount of a radioactive isotope (radionuclide) mixed with a radioluminescent phosphor chemical. The radioisotope continually decays, emitting radiation particles which strike molecules of the phosphor, exciting them to emit visible light.