|3D model (Jmol)||Interactive image|
|Molar mass||146.43 g/mol|
|Melting point||130 °C (266 °F; 403 K)|
|Boiling point||300 °C (572 °F; 573 K) (decomposes)|
|0.026 g/100 mL|
|Solubility||soluble in dilute acids|
Std enthalpy of
|US health exposure limits (NIOSH):|
|[1910.1027] TWA 0.005 mg/m3 (as Cd)|
IDLH (Immediate danger)
|Ca [9 mg/m3 (as Cd)]|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|what is ?)(|
Structure, preparation, and reactions
Cadmium hydroxide adopts the same structure as Mg(OH)2, consisting of slabs of octahedral metal centers surrounded by octahedral of hydroxide ligands.
It is produced by treating cadmium nitrate with sodium hydroxide:
- Cd(NO3)2 + 2 NaOH → Cd(OH)2 + 2 NaNO3
Attempted preparation from other cadmium salts is more complicated.
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 caustic soda solution. It forms complexes with cyanide, thiocyanate and ammonium ions when added to the solutions of these ions. 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:
- 2 NiO(OH) + 2 H2O + Cd → Cd(OH)2 + Ni(OH)2
- Zumdahl, Steven S. (2009). Chemical Principles 6th Ed. Houghton Mifflin Company. p. A21. ISBN 0-618-94690-X.
- "NIOSH Pocket Guide to Chemical Hazards #0087". National Institute for Occupational Safety and Health (NIOSH).
- Karl-Heinz Schulte-Schrepping, Magnus Piscator "Cadmium and Cadmium Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, 2007 Wiley-VCH, Weinheim. doi:10.1002/14356007.a04_499.
- Hemmingsen, L.; Bauer, R.; Bjerrum, M. J.; Schwarz, K.; Blaha, P.; Andersen, P., "Structure, Chemical Bonding, and Nuclear Quadrupole Interactions of β-Cd(OH)2: Experiment and First Principles Calculations", Inorganic Chemistry 1999, volume 38, 2860-2867. doi:10.1021/ic990018e