Zinc hydroxide
From Wikipedia, the free encyclopedia
| Zinc hydroxide | |
|---|---|
| Identifiers | |
| CAS number | [20427-58-1] |
| Properties | |
| Molecular formula | Zn(OH)2 |
| Molar mass | 99.39 g/mol |
| Appearance | white powder |
| Density | 3.053 g/cm3, solid |
| Melting point |
125°C (decomposition) |
| Solubility in water | Ksp = 4.5 x 10^-17 |
| Hazards | |
| EU classification | not listed |
| NFPA 704 |
 0
3
0
|
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references |
|
Zinc hydroxide Zn(OH)2 is an inorganic chemical compound.
It is unusual in that, like zinc oxide, it is amphoteric. Thus it will dissolve readily in a dilute solution of a strong acid, such as HCl, and also in a solution of sodium hydroxide.
It can be prepared by adding sodium hydroxide solution, but not in excess, to a solution of any zinc salt. A white precipitate will be seen: Zn2+ + 2OH- → Zn(OH)2.
If excess sodium hydroxide is added, the precipitate of zinc hydroxide will dissolve, forming a colourless solution of zincate ion: Zn(OH)2 + 2OH- → Zn(OH)42-. This property can be used as a test for zinc ions in solution, but it is not exclusive, since aluminum and lead compounds behave in a very similar manner.
One major use is as an absorbent in surgical dressings.
[edit] References
 |
This article does not cite any references or sources. (September 2007) Please help improve this article by adding citations to reliable sources. Unverifiable material may be challenged and removed. |
 |
This inorganic compound-related article is a stub. You can help Wikipedia by expanding it. |
