forms covalent bonds with most other elements, noting it can form ionic selenides with highly electropositive metals. The common oxide of selenium (SeO3)...

coinage metal selenides X2Se (X = Cu, Ag, Au) with soda ash to give the selenite: X2Se + O2 + Na2CO3 → Na2SeO3 + 2 X + CO2; the selenide is neutralized...

heavier hydrogen chalcogenides, namely hydrogen sulfide H2S, hydrogen selenide H2Se, and hydrogen telluride H2Te, water should be "a foul-smelling, poisonous...

S2CID 100301711. Kirby, HW (1985). "Analytical chemistry of astatine". In Kugler, HK; Keller, C (eds.). Gmelin Handbook of Inorganic Chemistry, At Astatine...