Names | |
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IUPAC name
Cadmium(II) hydroxide
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Identifiers | |
3D model (
JSmol)
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ChemSpider | |
ECHA InfoCard | 100.040.137 |
PubChem
CID
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UNII | |
CompTox Dashboard (
EPA)
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Properties | |
Cd(OH)2 | |
Molar mass | 146.43 g/mol |
Appearance | white crystals |
Density | 4.79 g/cm3 |
Melting point | 130 °C (266 °F; 403 K) |
Boiling point | 300 °C (572 °F; 573 K) (decomposes) |
0.026 g/100 mL | |
Solubility product (Ksp)
|
7.2×10−15 [1] |
Solubility | soluble in dilute acids |
-41.0·10−6 cm3/mol | |
Structure | |
hexagonal | |
Thermochemistry | |
Std molar
entropy (S⦵298) |
96 J·mol−1·K−1 [2] |
Std enthalpy of
formation (ΔfH⦵298) |
−561 kJ·mol−1 [2] |
Hazards | |
NIOSH (US health exposure limits): | |
PEL (Permissible)
|
[1910.1027] TWA 0.005 mg/m3 (as Cd) [3] |
REL (Recommended)
|
Ca [3] |
IDLH (Immediate danger)
|
Ca [9 mg/m3 (as Cd)] [3] |
Related compounds | |
Other
anions
|
Cadmium chloride, Cadmium iodide |
Other
cations
|
Zinc hydroxide, Calcium hydroxide, Magnesium hydroxide |
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
|
Cadmium hydroxide is an inorganic compound with the formula Cd(OH)2. It is a white crystalline ionic compound that is a key component of nickel–cadmium battery. [4]
Cadmium hydroxide adopts the same structure as Mg(OH)2, consisting of slabs of octahedral metal centers surrounded by octahedral of hydroxide ligands. [5]
It is produced by treating cadmium nitrate with sodium hydroxide:
Preparation has been achieved from some other cadmium salts, [6] [4]
Cd(OH)2 and cadmium oxide react equivalently. Cadmium hydroxide is more basic than zinc hydroxide. It forms the anionic complex [Cd(OH)42− when treated with concentrated base. It forms complexes with cyanide, thiocyanate, and ammonia.
Cadmium hydroxide loses water on heating, producing cadmium oxide. Decomposition commences at 130 °C and is complete at 300 °C. Reactions with mineral acids (HX) produce the corresponding cadmium salts (CdX2). With hydrochloric acid, sulfuric acid, and nitric acid, the products are cadmium chloride, cadmium sulfate, and cadmium nitrate, respectively.
It is generated in storage battery anodes, in nickel-cadmium and silver-cadmium storage batteries in its discharge: