Chromium(II) sulfide

Chromium(II) sulfide, also known as chromous sulfide, is an inorganic compound with the chemical formula CrS. It is a black solid that is insoluble in water and is known for its use in various industrial applications.

Structure and Properties

Chromium(II) sulfide is composed of chromium in the +2 oxidation state and sulfide ions. The compound crystallizes in a cubic structure similar to that of rock salt, with each chromium ion surrounded by six sulfide ions and vice versa. This structure is typical for many metal sulfides.

The compound is known for its high melting point of approximately 1550 °C, which makes it stable under a variety of conditions. Its density is about 4.63 g/cm³, and it is generally considered to be insoluble in water.

Synthesis

Chromium(II) sulfide can be synthesized through the direct combination of chromium and sulfur at high temperatures:

<math>\text{Cr} + \text{S} \rightarrow \text{CrS}</math>

Alternatively, it can be prepared by the reduction of chromium(III) sulfide using hydrogen gas:

<math>\text{Cr}_2\text{S}_3 + \text{H}_2 \rightarrow 2\text{CrS} + \text{H}_2\text{S}</math>

Applications

Chromium(II) sulfide is used in various industrial applications, particularly in the field of materials science. It is used as a pigment due to its black color and as a precursor for other chromium compounds. Additionally, it has potential applications in the field of semiconductors and catalysis.

Safety and Handling

As with many metal sulfides, chromium(II) sulfide should be handled with care. It is important to avoid inhalation of dust and to use appropriate personal protective equipment when handling the compound. Chromium compounds can be toxic, and proper disposal methods should be followed to minimize environmental impact.

Also see

• Chromium(III) sulfide
• Chromium compounds
• Sulfide minerals
• Inorganic chemistry