[4] Tellurium dichloride is a black solid that reacts with water.

It melts into a black liquid and vapourizes into a purple gas.

[5] Tellurium dichloride (TeCl2) is unstable with respect to disproportionation.

They are prepared by treating tellurium dioxide with hydrochloric acid in the presence of thioureas.

The thiourea serves both as a ligand and as a reductant, converting Te(IV) to Te(II).