Calcium |
| Symbol | Ca |
|---|---|
| Latin name | Calcium |
| Atomic number | 20 |
| Period | 4 |
| Element category | Alkaline earth metals |
| Relative atomic mass | 40.078 |
| Group | II.A |
| Electronegativity | 1.0 |
| Oxidation numbers | 2 |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s2 |
| Density [g/cm3] | 1.55 |
| State | Solid |
| Melting point [°C] | 839 |
| Boiling point [°C] | 1484 |
| Thermal conductivity [W m-1K-1] | 200 |
| Heat capacity [J K-1g-1] | 0.647 |
| Discovery | 1808 |
| Hardness [Mohs scale] | 1.5-2 |
| Brinell hardness [MPa] | 167 |
| Young's modulus [GPa] | 20 |
| Electrical conductivity [S m-1] | 3.13 · 107 |
| Shear modulus [GPa] | 7.4 |
| 1.st ionization energy [eV] | 6.1132 |
| 2.nd ionization energy [eV] | 11.871 |
| 3.rd ionization energy [eV] | 50.908 |
| Stable isotopes | 6 |
| Unstable isotopes | 8 |