What happens when tellurium(II) chloride reacts with water?

1 Answer
Dec 28, 2015

Tellurium(II) chloride is hydrolyzed by water.

Explanation:

Tellurium(II) chloride, #"TeCl"_2#, will be hydrolyzed by water to form tellurium metal, tellourous acid, #"H"_2"TeO"_3#, and hydrochloric acid, #"HCl"#.

The balanced chemical equation for this reaction looks like this

#2"TeCl"_text(2(s]) + 3"H"_2"O"_text((l]) -> "Te"_text((s]) + "H"_2"TeO"_text(3(aq]) + 4"HCl"_text((aq])#

An interesting thing to notice here is that tellurium, which exists in its #+2# oxidation state in tellurium(II) chloride, will be reduced to tellurium metal and oxidized to its #+4# oxidation state in tellorous acid.

This implies that you're dealing with a disproportionation reaction, which is the name given to a chemical reaction in which the same chemical species undergoes both oxidation and reduction.

I think that the same reaction pattern can be expected for tellurium(II) bromide, #"TeBr"_2#. The hydrolysis of this compound would produce hydrobromic acid, #"HBr"#, instead of hydrochloric acid

#2"TeBr"_text(2(s]) + 3"H"_2"O"_text((l]) -> "Te"_text((s]) + "H"_2"TeO"_text(3(aq]) + 4"HBr"_text((aq])#