Facts about the
Definition of the Element Selenium A non-metallic element, red in
powder form, black in vitreous form, and metallic gray in
crystalline form, resembling sulfur and obtained primarily as a
by-product of electrolytic copper refining. It is widely used in
rectifiers, as a semiconductor, and in xerography. Its
photovoltaic and photoconductive actions make it useful in
photocells, photographic exposure meters, and solar cells.
Interesting Facts
about the Origin and Meaning of the element name Selenium
What are the origins of the word Selenium ?
The name originates from the Greek word 'selene' meaning Moon.
Facts about the
Classification of the Element Selenium
Selenium is classified as an element in the 'Non-metals' section
which can be located in groups 14,15 and 16 of the Periodic Table.
Non-metals are not easily able to conduct electricity or heat and
do not reflect light . Non-metallic elements are very brittle, and
cannot be rolled into wires or pounded into sheets. Non-metallic
elements exist, at room temperature, in two of the three states of
matter : gases (such as oxygen) and solids (such as carbon).
Brief Facts about the
Discovery and History of the Element Selenium
Selenium was discovered by Jons Jacob Berzelius in 1817
Occurrence of the
element Selenium in
the Atmosphere
Occurs as selenide in many sulfide ores
Obtained primarily as a by-product of electrolytic copper refining
Common Uses of
Selenium
TV cameras
Xerography
Photographic equipment
The Properties of the Element Selenium
Name of Element : Selenium
Symbol of Element : Se
Atomic Number of Selenium : 34
Atomic Mass: 78.96 amu
Melting Point: 217.0 °C - 490.15 °K
Boiling Point: 684.9 °C - 958.05005 °K
Number of Protons/Electrons in Selenium : 34
Number of Neutrons in Selenium : 45
Crystal Structure: Hexagonal
Density @ 293 K: 4.79 g/cm3
Color of Selenium : gray, red & black
The element Selenium and the Periodic Table
Find out more facts about Selenium on the Periodic Table which
arranges every chemical element according to its atomic number, as
based on the periodic law, so that chemical elements with similar
properties are in the same column. Our Periodic Table is simple to
use - just click on the symbol for Selenium for additional facts and
info and for an instant comparison of the Atomic Weight, Melting
Point, Boiling Point and Mass - G/cc of Selenium with any other
element. An invaluable source for more interesting facts and
information about the Selenium element and as a Chemistry reference
guide.
Facts and Info about
the element Argon - IUPAC and the Modern Standardised Periodic Table
The Standardised Periodic Table in use today was agreed by the
International Union of Pure Applied Chemistry, IUPAC, in 1985
which includes the Selenium element. The famous Russian Scientist,
Dimitri Mendeleev, perceived the correct classification method of
"the periodic table" for the 65 elements which were known in his
time. Selenium was discovered by Jons Jacob Berzelius in 1817. The Standardised Periodic Table now recognises more periods
and elements than Dimitri Mendeleev knew in his day but still all
fitting into his concept of the "Periodic Table" in which
Selenium is
just one element that can be found.
