Calcium Oxide

[Andy Clift]

Andy Clift: /* Usage for Clay and Glaze */

<div>{{chembox
| Name = Calcium oxide
| ImageFile = Calcium-oxide-3D-vdW.png
| ImageSize = 200px
| ImageName = Calcium oxide
| IUPACName = Calcium oxide
| OtherNames = Quicklime, Burnt lime, Unslaked lime
| Section1 = {{Chembox Identifiers
| ChemSpiderID = 14095
| UNII = C7X2M0VVNH
| InChI = 1/Ca.O/rCaO/c1-2
| SMILES = [Ca]=O
| InChIKey = ODINCKMPIJJUCX-BFMVISLHAU
| CASNo = 1305-78-8
| CASNo_Ref = {{cascite}}
| PubChem = 14778
| RTECS = EW3100000
| UNNumber = 1910
| ATCvet = yes
| ATCCode_prefix = P53
| ATCCode_suffix = AX18
}}
| Section2 = {{Chembox Properties
| Formula = CaO
| MolarMass = 56.077 g/mol
| Appearance = White to pale yellow powder
| Density = 3.35 g/cm3
| Solubility = reacts
| MeltingPt = 2572 °C (2845 K)
| BoilingPt = 2850 °C (3123 K)
| pKa = 12.5
| Solvent1 = [[acids]], [[glycerol]], [[sugar|sugar solution]]
| Solubility1 = soluble
| Solvent2 = [[methanol]], [[diethyl ether]], [[1-Nonanol|n-octanol]]
| Solubility2 = insoluble
}}
| Section3 = {{Chembox Structure
| Structure = [[Sodium chloride|NaCl]]
}}
| Section7 = {{Chembox Hazards
| ExternalMSDS = [http://www.jtbaker.com/msds/englishhtml/c0462.htm]
| EUClass =
| EUIndex = Not listed
| RPhrases =
| SPhrases =
| NFPA-H = 3
| NFPA-F = 0
| NFPA-R = 2
| NFPA-O =
| FlashPt = Non-flammable
}}
| Section8 = {{Chembox Related
| OtherAnions = [[Calcium sulfide]]
[[Calcium hydroxide]]
| OtherCations = [[Beryllium oxide]]
[[Magnesium oxide]]
[[Strontium oxide]]
[[Barium oxide]]
}}
}}

'''Calcium oxide''' ('''CaO'''), commonly known as '''quicklime''' or '''burnt lime''', is a widely used [[chemical compound]]. It is a white, [[Caustic (substance)|caustic]], [[alkali]]ne [[crystal]]line solid at room temperature.

The broadly used term [[Lime (material)|'''lime''']] connotes calcium-containing inorganic materials, in which carbonates, oxides and hydroxides of calcium, silicon, magnesium, aluminum, & iron predominate, such as [[limestone]]. By contrast, '''quicklime''' specifically applies to a single chemical compound.

[[Calcium]] [[oxide]] is usually made by the thermal decomposition of materials such as [[limestone]], that contain [[calcium carbonate]] (CaCO3; mineral [[calcite]]) in a [[lime kiln]]. This is accomplished by heating the material to above 825 [[celsius|°C]],Merck Index of chemicals and Drugs , 9th edition monograph 1650 a process called [[calcination]] or ''lime-burning'', to liberate a molecule of [[carbon dioxide]] (CO2); leaving quicklime. The quicklime is not stable and, when cooled, will [[Spontaneous_process|spontaneously]] react with CO2 from the air until, after enough time, it is completely converted back to calcium carbonate.


==Usage in Ceramics==

==Other Usage==

Quicklime is relatively inexpensive. Both it and a chemical derivative (calcium hydroxide) are important commodity chemicals.

Quicklime produces [[heat]] [[energy]] by the formation of the hydrate, [[calcium hydroxide]], by the following equation:{{US patent|3955554}}, '' Solar heating system.''

:CaO (s) + H2O (l) {{eqm}} Ca(OH)2 (aq) (

More...

[Brandon Kevin]

Metal oxides are, for the most part, very thermally stable, and do not easily decompose with added heat. Calcium oxide is one of those substances. Even the metal oxides will eventually decompose to the elements when heated to a high enough temperature.