Ca(OH)₂Ca(OH)274.0900 g·mol⁻¹
Molar mass74.090 g·mol⁻¹calc 74.092 • Atomic weights: CIAAW 2021 (conventional atomic weights)
FormulaCa(OH)₂Ca(OH)2
Classbase • ionicsolid
| Element | Count | Mass (g/mol) | Mass % |
|---|---|---|---|
| Ca | 1 | 40.078 | 54.09% |
| O | 2 | 31.998 | 43.19% |
| H | 2 | 2.016 | 2.72% |
Physical properties
- State at STP
- solid
- Density
- 2.24 g·cm⁻³ (solid at 20 °C, 1 atm)
- Melting point
- 853 K (decomposes to CaO + H₂O)
- Boiling point
- —
Structure & bonding
Layered ionic Ca2+ with OH-; alkaline solution (limewater).
Occurrence & preparation
Slaking quicklime CaO + H2O -> Ca(OH)2; mineral portlandite.
Uses
- Construction (mortar)
- Water treatment
Safety
Caustic — irritates skin, eyes, lungs.
Consult current SDS. — consult current SDS before handling.