Calcium oxide
chemical compound
Calcium oxide is a chemical compound of calcium and oxygen. Its chemical formula is CaO. It is known as quicklime. It is made in a lime kiln. It releases heat when dissolved in water and changes into calcium hydroxide. It is a white powder.
| Names | ||
|---|---|---|
| IUPAC name Calcium oxide | ||
| Other names Quicklime, burnt lime, unslaked lime, pebble lime, calcia | ||
| Identifiers | ||
3D model (JSmol) | ||
| ChEBI | ||
| ChEMBL | ||
| ChemSpider | ||
| ECHA InfoCard | 100.013.763 | |
| E number | E529 (acidity regulators, ...) | |
| Gmelin Reference | 485425 | |
PubChem CID | ||
| RTECS number |
| |
| UNII | ||
| UN number | 1910 | |
CompTox Dashboard (EPA) | ||
SMILES
| ||
| Properties | ||
| CaO | ||
| Molar mass | 56.0774 g/mol | |
| Appearance | White to pale yellow/brown powder | |
| Odor | Odorless | |
| Density | 3.34 g/cm3[1] | |
| Melting point | 2,613 °C (4,735 °F; 2,886 K)[1] | |
| Boiling point | 2,850 °C (5,160 °F; 3,120 K) (100 hPa)[2] | |
| Reacts to form calcium hydroxide | ||
| Solubility in Methanol | Insoluble (also in diethyl ether, octanol) | |
| Acidity (pKa) | 12.8 | |
| −15.0×10−6 cm3/mol | ||
| Structure | ||
| Cubic, cF8 | ||
| Thermochemistry | ||
| Std enthalpy of formation ΔfH | −635 kJ·mol−1[3] | |
| Standard molar entropy S | 40 J·mol−1·K−1[3] | |
| Pharmacology | ||
ATCvet code | QP53AX18 (WHO) | |
| Hazards | ||
| NFPA 704 |
| |
| Flash point | Non-flammable | |
| U.S. Permissible exposure limit (PEL) | TWA 5 mg/m3[4] | |
| Related compounds | ||
| Other anions | Calcium sulfide Calcium hydroxide | |
| Other cations | Beryllium oxide Magnesium oxide Strontium oxide Barium oxide | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | ||
| Infobox references | ||
It is also a base. It reacts with acids to make calcium salts. Quicklime is an important ingredient of cement.
Related pages
References
🔥 Top keywords: Main PageSpecial:Search0Slash (punctuation)BlackSpecial:RecentChanges4 (number)DavidSOLID (object-oriented design)Wikipedia:AboutFile:Sexual intercourse with internal ejaculation.webmHelp:ContentsHelp:IntroductionLisa Sparxxx2023 UEFA Champions League FinalColour24-hour clockAdolf Hitler UunonaBismillahir Rahmanir Raheem6 (number)T. N. SeshanFile:ASCII-Table-wide.svg20 (number)Poor Things (movie)United StatesCristiano RonaldoList of people who have walked on the MoonAli Malikov50 (number)17 (number)The Valley (2024 TV series)GrassList of mathematical symbolsList of U.S. states and territories by time zone8 (number)List of countries by areaWikipedia:Simple talkList of largest Hindu templesRama
