Editing Neptunium (section)

===Chemical===
Neptunium has five ionic [[oxidation state]]s ranging from +3 to +7 when forming chemical compounds, which can be simultaneously observed in solutions. It is the heaviest actinide that can lose all its valence electrons in a stable compound. The most stable state in solution is +5, but the valence +4 is preferred in solid neptunium compounds. Neptunium metal is very reactive. Ions of neptunium are prone to hydrolysis and formation of [[coordination compound]]s.<ref name="Himiya neptuniya">{{cite book|title = Analytical chemistry of neptunium|editor=V. A. Mikhailov|place =Moscow |publisher = [[Nauka (publisher)|Nauka]]|date = 1971}}</ref>