Properties of thallium (I) sulfide:

Black with blue tint, soft and greasy to the touch (such as graphite), volatile. Poorly soluble in water. Does not form crystalline hydrates. Does not react with alkalis. Decomposed by acids. Easily oxidized in air.

Molar mass g/mol 440.83
Density g/cm3 8.39
Melting point °C 448.9
Boiling point °C 1177

Methods for preparation of thallium (I) sulfide:

2Tl + S = Tl2S (320° C, in the atm. of H2),

2Tl + 3S = Tl2S3 (200-250° C).

2TlNO3 + H2S = Tl2S↓ + 2HNO3.

Chemical reactions with thallium (I) sulfide:

Tl2S + 2HCl = 2TlCl↓ + H2S↑.

Tl2S + 4HNO3(conc., cold) = 2TlNO3 + 2NO2↑ + S↓ + 2H2O.

Tl2S + 18HNO3(conc., hot) = 2Tl(NO3)3 + 12NO2↑ + H2SO4 + 8H2O.

Tl2S + 2O2 = Tl2SO4 (250° C).


Did you know?

Hydrogen is the most abundant element. About 75% of the elemental mass of the universe is hydrogen.