Selenium

Selenium (pronounced /sɨˈliːniəm/ sə-LEE-nee-əm) is a chemical element with the atomic number 34, represented by the chemical symbol Se, an atomic mass of 78.96. It is a nonmetal, chemically related to sulfur and tellurium, and rarely occurs in its elemental state in nature. Isolated selenium occurs in several different forms, the most stable of which is a dense purplish-gray semi-metal (semiconductor) form that is structurally a trigonal polymer... more

Also known as:

  • Selenium, Se

Chemical Element

The 34th Element in the Periodic Table

← Previous

Arsenic

Arsenic (pronounced /ˈɑrsnɪk/, ARS-nik; also /ɑrˈsɛnɪk/, ar-SEN-ik when attributive) is the chemical element that has the symbol As, atomic number 33...

Next →

Bromine

Bromine (pronounced /ˈbroʊmiːn/ BROH-meen or /ˈbroʊmɨn/ BROH-min, from Greek: βρῶμος, brómos, meaning "stench (of he-goats)" ), is a chemical element...

View collection »

Symbol:

  • Se

Atomic mass:

Mass Uncertainty
  • 78.96 u (1.311E-16 µg )
  • 0.03 u (5E-20 µg )

Electrons per shell:

  • 2,8,18,6

Electron affinity:

Value Uncertainty
  • 2.02067 eV (0.00000202067 MeV )
  • 0.00002 eV (2E-11 MeV )

Electronegativity (Pauling scale):

  • 2.55

Atomic radius:

  • 115 pm (0.00000453 )

Covalent radius:

  • 1.16 pm (4.57E-8 )

Van der Waals radius:

  • 190 pm (0.00000748 )

Melting Point:

  • 220.85 °C (429.53 °F )

Boiling Point:

  • 684.85 °C (1264.7 °F )

Periodic table block:

Ionization Energy:

  • 9.7524 eV (0.0000097524 MeV )

Discovery Date:

  • 1817

Discovering Country:

Electron Configuration:

  • Ar 3d10 4s2 4p4
top ↑

We can also tell you Selenium is a…

If you know more about Selenium, you can add more facts here »

These people have edited this topic:

Edit this topic
Edit and Show details

Add or delete facts, download data in JSON or RDF formats, and explore topic metadata.

Freebase Logo
What is Freebase?

Freebase is a huge collection of facts, built by people like you. Freebase connects facts in ways other sites can't, giving you new ways to explore millions of subjects.
You can help improve it!

Freebase Attribution

Freebase data is free for use under the CC-BY license.

The original description for Selenium was automatically generated from Wikipedia.org licensed under the GNU Free Documentation License.
[1]
Learn more about Freebase licensing and attribution