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CaO
Calcium oxide
IUPAC : Calcium oxide
OxideIndustrialEveryday
Obtained by calcining limestone (CaCO₃) at ~900 °C, quicklime is one of the oldest and most produced materials in the world. It reacts vigorously with water to form slaked lime Ca(OH)₂.
3D ball-and-stick representation of Calcium oxide (formula CaO). Constituent atoms: Ca, O.
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Physical properties
Molar mass56.077 g/mol
State at 20 °Csolid
Density3.34 g/cm³
Melting point2886.00 K (2613 °C)
Boiling point3123.00 K (2850 °C)
Solubility (H₂O)réagit (1.19 g/L, forme Ca(OH)₂)
Structure
Crystal systemCubic
3D render modeBall-and-stick
Detailed description
Synthesis
Calcination of limestone in a lime kiln: CaCO₃ → CaO + CO₂. The process requires 900–1000 °C. World production > 300 Mt/yr.
Uses and applications
- Steelmaking (blast-furnace flux)
- Cement industry (main component of Portland clinker)
- Water and soil treatment (neutralisation)
- Agriculture (calcium liming)
- Pulp and paper industry
Safety (GHS)
GHS05 · CorrosiveGHS07 · Harmful / irritant
H statements : H315, H318, H335
Reacts exothermically with water (burn risk). Strong irritant to skin, eyes and respiratory tract.
Constituent elements
References
Sources : PubChem CID 14778 · CRC Handbook of Chemistry and Physics
Related processes
Industrial processes involving this compound.