Cobalt(II) oxide: Difference between revisions
imported>Paul Derry |
imported>Paul Derry No edit summary |
||
| Line 19: | Line 19: | ||
|- | |- | ||
| Appearance | | Appearance | ||
| A | | A grayish green powder | ||
|- | |- | ||
| [[CAS registry number|CAS number]] | | [[CAS registry number|CAS number]] | ||
| Line 73: | Line 73: | ||
|} | |} | ||
'''Cobalt(II) oxide''' is a grayish green powder used extensively in the [[ceramic]]s industry as an additive to create blue colored glazes and enamels as well as in the chemical production industry for producing cobalt(II) salts. | |||
'''Cobalt(II) oxide''' is a | |||
Cobalt(II) oxide is a product of [[cobalt(II,III) oxide|Cobalt(II,III) oxide]] decomposing at 895 °C through the reaction: | Cobalt(II) oxide is a product of [[cobalt(II,III) oxide|Cobalt(II,III) oxide]] decomposing at 895 °C through the reaction: | ||
| Line 94: | Line 93: | ||
==Health Concerns== | ==Health Concerns== | ||
This oxide is also found in cobalt dryers, additives to paints that can be found at most art stores. These dryers are considered highly toxic and a "possible human carcinogen" by the International Agency for Research on Cancer. Symptoms of acute exposure include coughing, wheezing and difficulty breathing. The small particles also pose the risk of ocular inflammation. The use of NIOSH approved respiratory equipment is recommended when handling this substance.<ref>American Chemical Society: "Journal of Chemical Education" Vol.28 No. 10 October 2001 "Hazardous Characteristics" <http://membership.acs.org/c/ccs/pubs/CLIPS/JCE20011328.pdf></ref> | This oxide is also found in cobalt dryers, additives to paints that can be found at most art stores. These dryers are considered highly toxic and a "possible human carcinogen" by the International Agency for Research on Cancer. Symptoms of acute exposure include coughing, wheezing and difficulty breathing. The small particles also pose the risk of ocular inflammation. The use of NFPA/NIOSH approved respiratory equipment is recommended when handling this substance.<ref>American Chemical Society: "Journal of Chemical Education" Vol.28 No. 10 October 2001 "Hazardous Characteristics" <http://membership.acs.org/c/ccs/pubs/CLIPS/JCE20011328.pdf></ref> | ||
===Toxicology=== | |||
LD50/LC50 tests indicate that in rats a dose of 202mg per kilogram given orally is fatal. In 1992 the State of California added Cobalt(II) oxide to its list of carcinogenic agents however RTECS does not officially list the oxide as a carcinogen.<ref>Fisher Scientific UK MSDS "Cobalt(II) oxide" § 11 'Toxicological Information'</ref> | |||
==Reactivity Concerns== | ==Reactivity Concerns== | ||
| Line 103: | Line 105: | ||
<references /> | <references /> | ||
[[Category:Cobalt compounds]] | [[Category:Cobalt compounds]] | ||
[[Category:Chemistry Workgroup]] | [[Category:Chemistry Workgroup]] | ||
[[Category:CZ Live]] | [[Category:CZ Live]] | ||
Revision as of 20:50, 8 April 2007
| Template:Chembox header | Cobalt(II) oxide | |
|---|---|
| Cobalt(II) oxide | |
| Template:Chembox header | General | |
| Systematic name | Cobalt(II) Oxide |
| Other names | Cobaltous Oxide, Cobalt Monoxide, Cobaltous Monoxide |
| Molecular formula | CoO |
| Molar mass | 74.93 g/mol |
| Appearance | A grayish green powder |
| CAS number | 1307-96-6 |
| Template:Chembox header | Properties | |
| Density and phase | 6.1 g/cm3 |
| Solubility in water | practically insoluble in water, soluble in strong acids |
| Melting point | 1933°C (2206 K) |
| Boiling point | ?°C (? K) |
| Template:Chembox header | Hazards | |
| MSDS | (Use CAS#) Fisher Scientific |
| Main hazards | Respiratory tract inflammation possibly carcinogenic |
| NFPA 704 | Template:NFPA 704 |
| R/S statement | R: 22 43 50-53 S: (2-)24-37-60-61 |
| RTECS number | GG2800000 |
| Template:Chembox header | Related compounds | |
| Other anions | Cobalt(II) carbonate Cobalt(II) nitrate, Cobalt(II) chloride |
| Other cations | Iron(III) oxide, Iron(II) oxide Cobalt(II,III) oxide |
| Related compounds | Cobalt(III) oxide |
| Template:Chembox header | Except where noted otherwise, data are given for materials in their standard state (at 25°C, 100 kPa) Infobox disclaimer and references | |
_oxide.jpg){kind=link}
Cobalt(II) oxide is a grayish green powder used extensively in the ceramics industry as an additive to create blue colored glazes and enamels as well as in the chemical production industry for producing cobalt(II) salts.
Cobalt(II) oxide is a product of Cobalt(II,III) oxide decomposing at 895 °C through the reaction:
- 2 Co3O4(s) → 6 CoO(s) + O2(g)
Cobalt(II) oxide is also a product of Cobalt(II) carbonate decomposing through the reaction:
- CoCO3(s) → CoO(s) + CO2(g)
Ceramics and Other Uses
Cobalt(II) Oxide has been used for centuries as a coloring agent on kiln fired ceramic glazes, the earliest examples go back to the beginnings of kiln fired pottery. Cobalt(II) Oxide colorants are stable and retain their coloration indefinitely. The oxide is one of the most powerful colorants commonly used in the making of glazes and slips and requires only 1 part oxide to 100,000 parts glazing compound to produce the deep blue shade commonly referred to as cobalt blue. By varying the temperature of the kiln, the potter can adjust the coloring of the oxide ranging anywhere from the familiar blue, to a shade nearing black. [1] Cobalt(II) oxide is also used in dryers used with oil based paints to expedite their curing. These substances can be found at most art stores.
Industrial Uses
As stated earlier, cobalt(II) oxide is used in the production of cobalt(II) salts such as CoCl2 and Co(NO3)2. Cobalt(II) oxide can also be found in animal feed and fertilizer as a supplement to aid in the production of Vitamin B12.
Health Concerns
This oxide is also found in cobalt dryers, additives to paints that can be found at most art stores. These dryers are considered highly toxic and a "possible human carcinogen" by the International Agency for Research on Cancer. Symptoms of acute exposure include coughing, wheezing and difficulty breathing. The small particles also pose the risk of ocular inflammation. The use of NFPA/NIOSH approved respiratory equipment is recommended when handling this substance.[2]
Toxicology
LD50/LC50 tests indicate that in rats a dose of 202mg per kilogram given orally is fatal. In 1992 the State of California added Cobalt(II) oxide to its list of carcinogenic agents however RTECS does not officially list the oxide as a carcinogen.[3]
Reactivity Concerns
Cobaltous Oxide rapidly decomposes hydrogen peroxide and oxidizes the drying of unsaturated oils in an exothermic reaction that can be potentially explosive. [4]
References
- ↑ Zamek, Jeff: "A Problem With Cobalt?" Ceramics Today http://www.ceramicstoday.com/articles/zamek_cobalt.htm
- ↑ American Chemical Society: "Journal of Chemical Education" Vol.28 No. 10 October 2001 "Hazardous Characteristics" <http://membership.acs.org/c/ccs/pubs/CLIPS/JCE20011328.pdf>
- ↑ Fisher Scientific UK MSDS "Cobalt(II) oxide" § 11 'Toxicological Information'
- ↑ American Chemical Society: "Journal of Chemical Education" Vol.28 No. 10 October 2001 "Hazardous Characteristics" <http://membership.acs.org/c/ccs/pubs/CLIPS/JCE20011328.pdf>