Tags: Chemical Compound, Chemical Substance.
Thallium(I) sulfate (Tl2SO4) or thallous sulfate is the sulfate salt of thallium in the common +1 oxidation state as indicated by the Roman numeral I. It is often referred to as simply thallium sulfate but it is more correct to add the I to specify the oxidation state given that thallium(III) sulfate also exists and has some laboratory uses. Thallium(I) sulfate is colorless odorless and tasteless but highly toxic.