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Names | |||
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Other names | |||
Identifiers | |||
1306-23-6 | |||
3D model (Jmol) | Interactive image | ||
ChemSpider | 7969586 | ||
ECHA InfoCard | 100.013.771 | ||
EC Number | 215-147-8 | ||
PubChem | 14783 | ||
RTECS number | EV3150000 | ||
UNII | 057EZR4Z7Q | ||
UN number | 2570 | ||
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Properties | |||
CdS | |||
Molar mass | 144.47 g·mol−1 | ||
Appearance | Yellow-orange to brown solid. | ||
Density | 4.826 g/cm3, solid. | ||
Melting point | 1,750 °C (3,180 °F; 2,020 K) 10 MPa | ||
Boiling point | 980 °C (1,800 °F; 1,250 K) (sublimation) | ||
insoluble | |||
Solubility | soluble in acid very slightly soluble in ammonium hydroxide |
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-50.0·10−6 cm3/mol | |||
Refractive index (nD)
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2.529 | ||
Structure | |||
Hexagonal, Cubic | |||
Thermochemistry | |||
Std molar
entropy (S |
65 J·mol−1·K−1 | ||
Std enthalpy of
formation (ΔfH |
−162 kJ·mol−1 | ||
Hazards | |||
Safety data sheet | ICSC 0404 | ||
EU classification (DSD)
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Carc. Cat. 2 Muta. Cat. 3 Repr. Cat. 3 Toxic (T) Dangerous for the environment (N) |
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R-phrases | R45, R22, R48/23/25, R62, R63, R68, R50/53 | ||
S-phrases | S53, S45, S61 | ||
NFPA 704 | |||
Flash point | Non-flammable | ||
Lethal dose or concentration (LD, LC): | |||
LD50 (median dose)
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7080 mg/kg (rat, oral) | ||
US health exposure limits (NIOSH): | |||
PEL (Permissible)
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[1910.1027] TWA 0.005 mg/m3 (as Cd) | ||
REL (Recommended)
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Ca | ||
IDLH (Immediate danger)
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Ca [9 mg/m3 (as Cd)] | ||
Related compounds | |||
Other anions
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Cadmium oxide Cadmium selenide |
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Other cations
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Zinc sulfide Mercury sulfide |
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Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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what is ?) | (|||
Infobox references | |||
Cadmium sulfide is the inorganic compound with the formula CdS. Cadmium sulfide is a yellow solid. It occurs in nature with two different crystal structures as the rare minerals greenockite and hawleyite, but is more prevalent as an impurity substituent in the similarly structured zinc ores sphalerite and wurtzite, which are the major economic sources of cadmium. As a compound that is easy to isolate and purify, it is the principal source of cadmium for all commercial applications. Its vivid yellow color led to its adoption as a pigment for the yellow paint "cadmium yellow" in the 18th century.
Cadmium sulfide can be prepared by the precipitation from soluble cadmium(II) salts with sulfide ion. This reaction has been used for gravimetric analysis and qualitative inorganic analysis.
The preparative route and the subsequent treatment of the product, affects the polymorphic form that is produced (i.e., cubic vs hexagonal). It has been asserted that chemical precipitation methods result in the cubic zincblende form.
Pigment production usually involves the precipitation of CdS, the washing of the solid precipitate to remove soluble cadmium salts followed by calcination (roasting) to convert it to the hexagonal form followed by milling to produce a powder. When cadmium sulfide selenides are required the CdSe is co-precipitated with CdS and the cadmium sulfoselenide is created during the calcination step.
Cadmium sulfide is sometimes associated with sulfate reducing bacteria.
Special methods are used to produce films of CdS as components in some photoresistors and solar cells. In the chemical bath deposition method, thin films of CdS have been prepared using thiourea as the source of sulfide anions and an ammonium buffer solution to control pH:
Cadmium sulfide can be produced using metalorganic vapour phase epitaxy and MOCVD techniques. This process requies volatile cadmium and sulfur precursors. A common example is the reaction of dimethylcadmium with diethyl sulfide: