O
Oxygen Symbol (O)
Oxygen is element 8 of the periodic table. Copy its symbol O and see its atomic weight, electron configuration and common compounds.
What does O mean?
O is the chemical symbol for oxygen, element number 8 in the periodic table. Oxygen is a reactive nonmetal in group 16, period 2. It is about 21% of the atmosphere; it is needed for respiration and combustion.
Codes and properties
| Chemical symbol | O |
|---|---|
| Atomic number (Z) | 8 |
| Standard atomic weight | 15.999 |
| Group / period | 16 / 2 |
| Element category | reactive nonmetal |
| Electron configuration | 1s² 2s² 2p⁴ |
| Common compounds | O₂, H₂O, O₃, CO₂ |
How to type O
- Plain text: type
O— element symbols are ordinary Latin letters, with the first letter capitalised. - Subscripts in formulas: use Unicode subscript digits (₀₁₂₃₄₅₆₇₈₉) for formulas such as O₂ — copy them from the chemistry keyboard.
- LaTeX: write
\mathrm{O}in math mode, or use the mhchem package:\ce{O}. - HTML:
O; for subscripts use<sub>, e.g.H<sub>2</sub>O.
Frequently asked questions
What is the chemical symbol for oxygen?
The chemical symbol for oxygen is O.
What is the atomic number of oxygen?
Oxygen has atomic number 8, meaning each atom has 8 protons.
What is the electron configuration of oxygen?
The ground-state electron configuration of oxygen is 1s² 2s² 2p⁴.