CaCO₃
Compound · Salt
Calcium carbonate
碳酸钙
Calcium carbonate (碳酸钙), formula CaCO₃, is a salt with a molar mass of 100.09 g/mol (CAS 471-34-1). White solid, poorly soluble; insoluble in water; dissolves in co₂-rich water as calcium bicarbonate.
Key facts
| Molar mass | 100.09 g/mol |
|---|---|
| Category | Salt |
| State at 25°C | Solid |
| CAS | 471-34-1 |
Structure
Ca²⁺ [CO₃]²⁻
Ionic compound; main component of limestone and marble
Physical properties
| Appearance | White solid, poorly soluble |
|---|---|
| Melting point | 825 °C (分解) |
| Boiling point | — |
| Density | 2.71 g/cm³ |
| Solubility | Insoluble in water; dissolves in CO₂-rich water as calcium bicarbonate |
Key reactions
CaCO₃ →(高温) CaO + CO₂↑
Calcination — industrial quicklime production
CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂↑
Reacts with acid, releasing CO₂
Main uses
- Cement, lime and building materials
- Filler in plastics, rubber and paper
- Calcium supplement and antacid
Hazard
LowNon-toxic; heavy dust can irritate the airways
Constituent elements
Data sources
Molar mass is computed from IUPAC (CIAAW) standard atomic weights; formula, properties and reactions can be verified on PubChem, NIST and Wikipedia. The CAS number is the substance's unique registry identifier. Educational reference only.