Ca
Calcium Symbol (Ca)
Calcium is element 20 of the periodic table. Copy its symbol Ca and see its atomic weight, electron configuration and common compounds.
What does Ca mean?
Ca is the chemical symbol for calcium, element number 20 in the periodic table. Calcium is an alkaline earth metal in group 2, period 4. It is the main mineral in bones and teeth, and in limestone and chalk (CaCO₃).
Codes and properties
| Chemical symbol | Ca |
|---|---|
| Atomic number (Z) | 20 |
| Standard atomic weight | 40.078 |
| Group / period | 2 / 4 |
| Element category | alkaline earth metal |
| Electron configuration | 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² |
| Common compounds | CaCO₃, CaO, Ca(OH)₂ |
How to type Ca
- Plain text: type
Ca— element symbols are ordinary Latin letters, with the first letter capitalised and the second lowercase. - Subscripts in formulas: use Unicode subscript digits (₀₁₂₃₄₅₆₇₈₉) for formulas such as CaCO₃ — copy them from the chemistry keyboard.
- LaTeX: write
\mathrm{Ca}in math mode, or use the mhchem package:\ce{Ca}. - HTML:
Ca; for subscripts use<sub>, e.g.H<sub>2</sub>O.
Frequently asked questions
What is the chemical symbol for calcium?
The chemical symbol for calcium is Ca.
What is the atomic number of calcium?
Calcium has atomic number 20, meaning each atom has 20 protons.
What is the electron configuration of calcium?
The ground-state electron configuration of calcium is 1s² 2s² 2p⁶ 3s² 3p⁶ 4s².