Reactions of Elemental Selenium and Tellurium

Selenium and tellurium are rather reactive elements, and they combine readily with a variety of metals and nonmetals. For example, they readily bum to produce the dioxides  

Reactions with metals produce selenides and tellurides as illustrated by the reactions 

Reactions with halogens can produce a variety of products depending on the relative amounts of the reactants and the reaction conditions  

The elements also react with cyanide ion to form the selenocyanate and tellurocyanate ions  

Cationic species containing selenium and tellurium can be obtained by the reactions 

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