Editing Americium (section)

===Oxygen compounds===
Three americium oxides are known, with the oxidation states +2 (AmO), +3 (Am<sub>2</sub>O<sub>3</sub>) and +4 (AmO<sub>2</sub>). [[Americium(II) oxide]] was prepared in minute amounts and has not been characterized in detail.<ref>{{Cite journal| doi = 10.1016/0022-1902(67)80191-X| title = A note on AmN and AmO| journal = Journal of Inorganic and Nuclear Chemistry| volume = 29| issue = 10| pages = 2650–2652| year = 1967| last1 = Akimoto | first1 = Y.}}</ref> [[Americium(III) oxide]] is a red-brown solid with a melting point of 2205&nbsp;°C.<ref name = "HOWI_1972">Wiberg, p. 1972</ref> [[Americium(IV) oxide]] is the main form of solid americium which is used in nearly all its applications. As most other actinide dioxides, it is a black solid with a cubic ([[fluorite]]) crystal structure.<ref name="g1267">Greenwood, p. 1267</ref>

The oxalate of americium(III), vacuum dried at room temperature, has the chemical formula Am<sub>2</sub>(C<sub>2</sub>O<sub>4</sub>)<sub>3</sub>·7H<sub>2</sub>O. Upon heating in vacuum, it loses water at 240&nbsp;°C and starts decomposing into AmO<sub>2</sub> at 300&nbsp;°C, the decomposition completes at about 470&nbsp;°C.<ref name="p4" /> The initial oxalate dissolves in nitric acid with the maximum solubility of 0.25&nbsp;g/L.<ref name="p5">Penneman, p. 5</ref>