Title: Cuprous Sulfide
CAS Registry Number: 22205-45-4
Molecular Formula: Cu2S
Molecular Weight: 159.16
Percent Composition: Cu 79.85%, S 20.15%
Literature References: Occurs in nature as the mineral chalcocite also called copper glance (grey, black, green, blue, or violet rhombic crystals). Prepn: Glemser, Sauer in Handbook of Preparative Inorganic Chemistry vol. 2, G. Brauer, Ed. (Academic Press, New York, 2nd ed., 1965) p 1016.
Properties: Blue to grayish-black lustrous powder, granules, or orthorhombic crystals. mp ~1100°. d420 5.6. On heating in the absence of air it forms Cu and CuS; in the presence of air it forms CuO, CuSO4 and SO2. Practically insol in water, acetic acid; very sparingly sol in HCl; dec by HNO3, concd H2SO4. Partially sol in NH4OH, readily in cyanide solns due to complex ion formation.
Melting point: mp ~1100°
Density: d420 5.6
Use: In luminous paints; in electrodes for thermoelements; in preparation of CuSO4; in solid-lubricant compositions; as catalyst.