34Se
Element 34
Selenium
Nonmetals
Selenium is a chemical element with symbol Se and atomic number 34.
Key data
- Atomic number
- 34
- Atomic mass
- 78.972 u
- Group / Period
- 16 / 4
- Block
- p-block
- Phase at STP
- Solid
- Density
- 4.81 g/cm³
- Melting point
- 220.9 °C
- Boiling point
- 684.9 °C
- Electron configuration
- [Ar] 3d10 4s2 4p4
Common uses
- •Glass tinting
- •Photocopiers
- •Antioxidant supplements
Discovery
Year: 1817
Discovered by: Jöns Jakob Berzelius
Frequently asked questions
What is the atomic number of Selenium?
Selenium has atomic number 34. Its symbol is Se and its atomic mass is 78.972 u.
What category of element is Selenium?
Selenium is classified as nonmetals. It sits in group 16, period 4 of the periodic table.
What is Selenium used for?
Common uses of Selenium include: Glass tinting, Photocopiers, Antioxidant supplements.
When was Selenium discovered?
Selenium was discovered in 1817 by Jöns Jakob Berzelius.
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