Se
Selenium Symbol (Se)
Selenium is element 34 of the periodic table. Copy its symbol Se and see its atomic weight, electron configuration and common compounds.
What does Se mean?
Se is the chemical symbol for selenium, element number 34 in the periodic table. Selenium is a nonmetal in group 16, period 4. It is a nonmetal that is an essential trace nutrient and is used in photocopier drums and glass.
Codes and properties
| Chemical symbol | Se |
|---|---|
| Atomic number (Z) | 34 |
| Atomic weight (PubChem) | 78.97 |
| Group / period | 16 / 4 |
| Element category | nonmetal |
| Electron configuration | [Ar]4s² 3d¹⁰ 4p⁴ |
| State at 20 °C | Solid |
| Oxidation states | +6, +4, -2 |
| Electronegativity (Pauling) | 2.55 |
| Melting point | 493.65 K (220.50 °C) |
| Boiling point | 958 K (684.85 °C) |
| Density | 4.809 g/cm³ |
| Discovered | 1817 |
| Common compounds | SeO₂, H₂Se |
How to type Se
- Plain text: type
Se— 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 SeO₂ — copy them from the chemistry keyboard.
- LaTeX: write
\mathrm{Se}in math mode, or use the mhchem package:\ce{Se}. - HTML:
Se; for subscripts use<sub>, e.g.H<sub>2</sub>O.
Frequently asked questions
What is the chemical symbol for selenium?
The chemical symbol for selenium is Se.
What is the atomic number of selenium?
Selenium has atomic number 34, meaning each atom has 34 protons.
What is the electron configuration of selenium?
The ground-state electron configuration of selenium is [Ar]4s² 3d¹⁰ 4p⁴.
Related symbols
Keep exploring
Reference: Selenium on PubChem (NIH)