Plutonium compounds

At room temperature, pure plutonium is silvery in color but gains a tarnish when oxidized.

[11] If the metal is exposed long enough to a limited amount of water vapor, a powdery surface coating of PuO2 is formed.

The metal reacts with the halogens, giving rise to compounds with the general formula PuX3 where X can be F, Cl, Br or I and PuF4 is also seen.

[2][10] The organometallic chemistry of plutonium complexes is typical for organoactinide species; a characteristic example of an organoplutonium compound is plutonocene.

[12][14] Powders of plutonium, its hydrides and certain oxides like Pu2O3 are pyrophoric, meaning they can ignite spontaneously at ambient temperature and are therefore handled in an inert, dry atmosphere of nitrogen or argon.

Refractory metals such as tantalum and tungsten along with the more stable oxides, borides, carbides, nitrides and silicides can tolerate this.