Atomic Properties
- Atomic Number
- 20
- Atomic Mass
- 40.0780 u
- Electron Configuration
- [Ar] 4s2
- Electronegativity
- 1.00
- Block
- s-block
- Group
- 2
- Period
- 4
Physical Properties
- Phase (STP)
- solid
- Melting Point
- 1115.00 K
- Boiling Point
- 1757.00 K
- Density
- 1.5500 g/cm³
About Calcium
Essential for bones and teeth; fifth most abundant element in body.
Isotopes of Calcium
Calcium has 6 naturally occurring isotopes.
| Isotope | Mass Number | Atomic Mass (u) | Abundance | Type |
|---|---|---|---|---|
| 40Ca | 40 | 39.96259086 | 96.94% | Stable |
| 42Ca | 42 | 41.95861783 | 0.6470% | Stable |
| 43Ca | 43 | 42.95876644 | 0.1350% | Stable |
| 44Ca | 44 | 43.95548156 | 2.086% | Stable |
| 46Ca | 46 | 45.953689 | 4.00e-3% | Stable |
| 48Ca | 48 | 47.95252276 | 0.1870% | Stable |
Data source: NIH PubChem (aggregated from IUPAC, NIST)