What is Neptunium?
[[File:Neptunium2.jpg|thumb|neptunium]] [[File:Neptune - Voyager 2 (29347980845) flatten crop.jpg|thumb|The planet [[Neptune]], which neptunium is named after]] '''Neptunium''' is a [[chemical]] [[Chemical element|element]] that has the symbol '''Np''' on the [[periodic table]]. It has the atomic number 93 which means it has 93 [[proton]]s and [[electron]]s in its [[atom]]s. It is named after the [[planet]] [[Neptune (planet)|Neptune]] in the same way as [[Uranium]] is named after the planet [[Uranus]]. == History == Neptunium was discovered in the year of 1940 by two men named Edwin McMillan and Phillip H. Abelson at Berkeley Radiation Center of the [[University of California]].<ref>{{Cite journal|last1=McMillan|first1=Edwin|last2=Abelson|first2=Philip Hauge|date=1940-06-15|title=Radioactive Element 93|url=https://link.aps.org/doi/10.1103/PhysRev.57.1185.2|journal=Physical Review|volume=57|issue=12|pages=1185–1186|doi=10.1103/PhysRev.57.1185.2}}</ref> It was created by fusing Hydrogen nuclei called protons into the element Uranium. == Chemistry == Neptunium is a radioactive silvery-metallic element that is part of a group of elements called the Actinides, which it shares many similarities to. Its melting point is 637 degrees Celsius, its boiling point is 4000 degrees Celsius, and its atomic mass is 237. It oxidizes very quickly with multiple different oxidation states. It also bonds with halides and even alkali metals. == Occurence == Since all isotopes of neptunium have half-lives that are many times shorter than the age of the Earth, any neptunium that was made when the earth was formed should have decayed by now. After only about 80 million years, the concentration of even the longest-lived isotope, <sup>237</sup>Np, would have been reduced to less than one-trillionth (10<sup>−12</sup>) of its original amount. == References == <references /> {{Periodic Table}} [[Category:Actinides]] [[Category:Synthetic elements]]