Copper(I) sulfide | |
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Copper(I) sulfide |
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Other names
Cuprous sulfide |
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Identifiers | |
CAS number | 22205-45-4 |
PubChem | 62755 |
ChemSpider | 8305611 |
ChEBI | CHEBI:51114 |
RTECS number | GL8910000 |
Jmol-3D images | Image 1 |
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Properties | |
Molecular formula | Cu2S |
Molar mass | 159.16 g/mol |
Density | 5.6 g/cm3 [1] |
Melting point |
1130 °C[2] |
Solubility in water | Insoluble |
Solubility | slightly soluble in HCl; soluble in NH4OH; dissolves in KCN; decomposes in HNO3, H2SO4 |
Hazards | |
EU Index | Not listed |
Flash point | Non-flammable |
Related compounds | |
Other anions | Copper(I) oxide Copper(I) selenide |
Other cations | Nickel(II) sulfide Copper(II) sulfide Zinc sulfide |
(verify) (what is: / ?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) |
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Infobox references |
Copper(I) sulfide is a copper sulfide, a chemical compound of copper and sulfur. It has the chemical compound Cu2S. It is found in nature as the mineral chalcocite. It has a narrow range of stoichiometry ranging from Cu1.997S to Cu2.000S[3].
Contents |
Cu2S can be prepared by heating copper strongly in sulfur vapour or H2S[2]. The reaction of copper powder in molten sulfur rapidly produces Cu2S, whereas pellets of copper require much higher temperature[4] Cu2S reacts with oxygen to form SO2:[5]
In the production of copper two thirds of the molten copper sulfide is oxidised as above, and the Cu2O reacts with unoxidised Cu2S to give Cu metal:[5]
There are two forms of Cu2S a low temperature monoclinic form ("low-chalcocite") which has a complex structure with 96 copper atoms in the unit cell[6] and a hexagonal form stable above 104°C.[7] In this structure there are 24 crystallographically distinct Cu atoms and the structure has been described as approximating to a hexagonal close packed array of sulfur atoms with Cu atoms in planar 3 coordination. This structure was initially assigned an orthorhombic cell due to the twinning of the sample crystal.
There is also a crystallographically-distinct phase (the mineral djurleite) with stoichiometry Cu1.96S which is non-stoichiometric (range Cu1.934S-Cu1.965S) and has a monoclinic structure with 248 copper and 128 sulfur atoms in the unit cell [6]. Cu2S and Cu1.96S are similar in appearance and hard to distinguish one from another.[8]
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