Selenium

Domain	Definitions
Chemistry	Chemical element:atomic number 34. Source: European Union. (references)
Health	An element with the atomic symbol Se, atomic number 34, and atomic weight 78.96. It is an essential micronutrient for mammals and other animals but is toxic in large amounts. Selenium protects intracellular structures against oxidative damage. It is an essential component of glutathione peroxidase. (references)
Mining	A nonmetallic element and member of the sulfur family. Symbol, Se. It is widely distributed in small quantities, usually as selenides of heavy metals. Obtained from electrolytic copper refining. Used in photocells, exposure meters, and solar cells, and extensively in rectifiers. (references)
Physics	Non-metallic element having the property that its electrical resistance varies inversely with incident light; used in multicrystalline form to make various devices; e. g. electrical rectifiers and photoresistive elements. Source: European Union. (references)
Source: compiled by the editor from various references; see credits.

Specialty Definition: Selenium

Arsenic - Selenium - Bromine

S
Se
Te

Full table

General

Name, Symbol, Number Selenium, Se, 34

Series Nonmetals

Group, Period, Block 16 (VIA), 4 , p

Density, Hardness 4790 kg/m³(300K), 2

Appearance grey, metallic lustre

Atomic Properties

Atomic weight 78.96 amu

Atomic radius (calc.) 115 (103) pm

Covalent radius 116 pm

van der Waals radius 190 pm

Electron configuration [Ar]3d3d¹⁰4p⁴4s²

e^- 's per energy level 2, 8, 18, 6

Oxidation states (Oxide) ±2,4,6 (strong acid)

Crystal structure Hexagonal

Physical Properties

State of matter solid (__)

Melting point 494 K (430 °F)

Boiling point 957.8 K (1265 °F)

Molar volume 16.42 ×1010^-3 m³/mol

Heat of vaporization 26.3 kJ/mol

Heat of fusion 6.694 kJ/mol

Vapor pressure 0.695 Pa at 494 K

Speed of sound 3350 m/s at 293.15 K

Miscellaneous

Electronegativity 2.48 (Pauling scale)

Specific heat capacity 320 J/(kg*K)

Electrical conductivity 1.0E^-10 10⁶/m ohm

Thermal conductivity 2.04 W/(m*K)

1^st ionization potential 941 kJ/mol

2^nd ionization potential 2045 kJ/mol

3^rd ionization potential 2973.7 kJ/mol

4^th ionization potential 4144 kJ/mol

Most Stable Isotopes

iso NA half-life DM DE MeV DP

⁷²Se {syn.} 8.4 d &Epsilon 0.335 ⁷²As

⁷⁴Se 0.87% Se is stable with 40 neutrons

⁷⁵Se {syn.} 119.779 d Ε 0.864 ⁷⁵As

⁷⁶Se 9.36% Se is stable with 42 neutrons

⁷⁷Se 7.63% Se is stable with 43 neutrons

⁷⁸Se 23.78% Se is stable with 44 neutrons

⁷⁹Se {syn.} 1.13 E⁶ y &beta 0.151 ⁷⁹Br

⁸⁰Se 49.61% Se is stable with 46 neutrons

⁸²Se 8.73% 1.08 E²⁰ y β 2.995 ⁸²Kr

SI units & STP are used except where noted.

Selenium is a chemical element in the periodic table that has the symbol Se and atomic number 34. This is a toxic nonmetal that is chemically related to sulfur and tellurium. It occurs in several different forms but one of these is a stable gray metallike form that conducts electricity better in the light than in the dark and is used in photocells. This element is found in sulfide ores such as pyrite.

Notable Characteristics

Selenium exists in a number of allotropic forms. In the powdered form, amorphous selenium is red, while the vitreous form is black. Crystalline hexagonal selenium is a metallic gray, while the monoclinic crystal is a deep red color.

It also exhibits a photovoltaic effect, converting light to electricity, and a photoconductive effect, electrical conductance increasing as selenium is exposed to light. Below its melting point, selenium is a p type semiconductor.

Applications

Selenium is an essential micronutrient in all known forms of life; it is a component of the unusual amino acid selenocysteine. Because of its photovoltaic and photoconductive properties, selenium is used extensively in electronics, such as photo cells, and solar cells. Selenium is also extensively used in rectifiers.

Selenium is used to remove color from glass, as it will counteract the green color ferrous impurities impart. It also can be used to give a red color to glasses and enamels. Selenium is used to improve the abrasion resistance in vulcanized rubbers. It also finds application in photocopying.

Another use for selenium is the toning of photographs, and is sold by numerous photographic manufacturers including Kodak and Fotospeed. Its artistic use is to intensify and extend the tonal range of black and white photographic images, and it can also be used for increasing the permanence of images.

History

Selenium (Latin selene meaning "Moon") was discovered in 1817 by Jons Jacob Berzelius who found the element associated with tellurium.

Growth in selenium consumption was driven by the development of new uses, including applications in rubber compounding, steel alloying, and selenium rectifiers. By 1970, selenium in rectifiers had largely been replaced by silicon, but its use as a photoconductor in plain paper copiers had become its leading application. During the 1980s, the photoconductor application declined (although it was still a large end-use) as more and more copiers using organic photoconductors were produced. In 1996, continuing research showed a positive correlation between selenium supplementation and cancer prevention in humans, but widespread direct application of this important finding would not add significantly to demand owing to the small doses required. In the late 1990s, the use of selenium (usually with bismuth) as an additive to plumbing brasses to meet no-lead environmental standards became important.

Occurrence

Selenium occurs as selenide in many sulfide ores, such as those of copper, silver, or lead. It is obtained as a byproduct of the processing of these ores, from the anode mud of copper refineries and the mud from the lead chambers of sulfuric acid plants. These muds can be processed by a number of means to obtain free selenium.

Isotopes

Selenium has 28 isotopes, of which 5 are stable.

Precautions

While free selenium is nontoxic, many of its compounds are extremely toxic, and have modes of action similar to that of arsenic. Hydrogen selenide and other compounds are very toxic. Plants grown in selenium-rich soils, such as locoweed, can cause serious effects on animals feeding on the plants.

Selenium and health

Selenium is a trace element in humans. It is used in free radical elimination and other antioxidant enzymes, and also plays a role in the functioning of the thyroid gland. Dietary selenium comes from cereals, meat, fish, and eggs.

Selenium deficiency in healthy people is extremely rare. It can occur in patients with severly compromised intestinal function, or those undergoing total parenteral nutrition. The recommended dietary allowance for adults is 55 micrograms per day. More than 400 micrograms per day can lead to toxicity (selenosis).

External Links

Commercial Usage: Selenium

Domain	Title
References	The World Market for Selenium, Tellurium, Phosphorus, Arsenic, and Boron: A 2004 Global Trade Perspective (reference) (more reference examples)

Books	Comprehensive Organic Chemistry : Sulphur, Selenium, Silicon, Boron, Organometallic Compounds (reference) Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids: A Report of the Panel on Dietary Antioxidants and Related Compounds, s (reference) Optical Resolution Procedures for Chemical Compounds: Compounds Containing a Sulfur or Selenium Sterocenter/Volume 4 (reference) Organic Compounds of Sulphur, Selenium & Tellurium (reference) Organic Selenium Compounds: Their Chemistry and Biology. (reference) (more book examples)
Source: compiled by the editor from various references; see credits.

Non-Fiction Usage: Selenium

Subject	Topic	Quote
Health		Selenium protects intracellular structures against oxidative damage. (references)
		Many substances that cause inflammation have been associated with the development of BPD. Magnesium, selenium, and copper deficiencies have also been suggested as possible factors. (references)
Economic History	Zambia	Zambia also has deposits of gold, silver, selenium, talc, limestone, coal, clay graphite, and silica. (references)
Source: compiled by the editor from ICON Group International, Inc.; see credits.

Usage Frequency: Selenium

Expressions: Selenium

Frequency of Internet Keywords: Selenium

Modern Translations: Selenium

Language		Translations for "selenium"; alternative meanings/domain in parentheses.
Albanian		selen. (various references)

Arabic		‏عنصر السيلينيوم. (various references)

Bulgarian		селен. (various references)

Chinese		�' . (various references)

Czech		selen. (various references)

Danish		selen. (various references)

Dutch		selenium, seleen. (various references)

Finnish		seleeni. (various references)

French		sélénium. (various references)

German		Selen. (various references)

Greek		σελήνιο. (various references)

Hungarian		szelén. (various references)

Italian		selenio. (various references)

Japanese Kanji		セル付 (10^-2, a center, bottle cap, celery, cellophane tape, center, centering, centi-, centimeter, centre, ceremony, facility providing funeral services, good sense, Scotch tape, select, selection, selector, sensation, sensational, sensor, serenade, stopper, with a self-starter). (various references)

Japanese Katakana		セレン . (various references)

Korean		셀� �. (various references)

Pig Latin		eleniumsay

Portuguese		selênio, selénio. (various references)

Romanian		seleniu. (various references)

Russian		селен. (various references)

Serbo-Croatian		selen. (various references)

Spanish		selenio. (various references)

Swedish		selen. (various references)

Turkish		selenyum. (various references)

Ukranian		селен. (various references)
Source: compiled by the editor from various translation references.

Derivations & Misspellings: Selenium

Rhyming with "Selenium"

# of Phoneme Matches	Pronunciation	Word(s) rhyming with "selenium" (pronounced sulē"nēum)
4	-n ē u m	ammonium, condominium, geranium, gonium, hafnium, harmonium, millennium, minium, neptunium, pandemonium, plutonium, polonium, titanium, uranium, zirconium.
3	-ē u m	alluvium, aquarium, atrium, auditorium, axiom, bacterium, barium, beryllium, cadmium, calcium, cesium, chromium, colloquium, compendium, consortium, crematorium, delirium, deuterium, disequilibrium, emporium, equilibrium, europium, fermium, gallium, gymnasium, helium, Herbarium, holmium, honorarium, idiom, indium, iridium, lawrencium, linoleum, lithium, magnesium, medium, moratorium, myocardium, nephridium, niobium, nobelium, opium, opprobrium, osmium, palladium, paramecium, petroleum, planetarium, Plasmodium, podium, potassium, premium, presidium, promethium, protium, psyllium, radium, requiem, rhodium, sodium, stadium, strontium, superpremium, symposium, tedium, tellurium, thallium, thorium, tritium, vanadium, yttrium.
Source: compiled by the editor (additional references); see credits.

Anagrams: Selenium

Scrabble® Enable2K-Verified Anagrams
	Words within the letters "e-e-i-l-m-n-s-u"
	-2 letters: elemis, enisle, ensile, limens, linums, lumens, lunies, muesli, muslin, neumes, senile, simnel.
	-3 letters: elemi, emeus, ensue, ileum, ileus, lenes, lenis, lense, liens, lieus, limen, limes, limns, lines, linum, lumen, lunes, mense, menus, mesne, miens, miles, mines, minus, mules, munis, neems, neume, neums, seine, semen, slime, smile.
	-4 letters: eels, elms, else, emes, emeu, emus.
	Words containing the letters "e-e-i-l-m-n-s-u"
	+1 letter: demilunes, luminesce, relumines, seleniums.
	+2 letters: luminesced, luminesces, mousseline, multisense, unseemlier.
	+3 letters: contumelies, disseminule, luminescent, lumpinesses, mousselines, multiscreen, neurilemmas, sublimeness, unblemished, unseemliest, untimeliest.
	+4 letters: beguilements, clumsinesses, disseminules, immensurable, luminescence, mendeleviums, mercifulness, mulishnesses, multiengines, numerologies, ultimateness, unseemliness, untimeliness, volunteerism.
	+5 letters: ceremoniously, crumblinesses, ecumenicalism, feuilletonism, immutableness, impulsiveness, luminescences, lumpishnesses, melodiousness, mercurialness, mindfulnesses, miscellaneous, multivalences, pumpernickels, sublimenesses, supplementing, unembellished, unmanlinesses, unsentimental, volunteerisms.
Source: compiled by the editor from various references; see credits. SCRABBLE® is a registered trademark. All intellectual property rights in and to the game are owned in the U.S.A and Canada by Hasbro Inc., and throughout the rest of the world by J.W. Spear & Sons Limited of Maidenhead, Berkshire, England, a subsidiary of Mattel Inc. Mattel and Spear are not affiliated with Hasbro.

Alternative Orthography: Selenium

Hexadecimal (or equivalents, 770AD-1900s) (references)

53 65 6C 65 6E 69 75 6D

Leonardo da Vinci (1452-1519; backwards) (references)

American Sign Language (origins from 1620-1817 in Italy and, especially, France) (references)

⁼

Semaphore (1791, in France) (references)

Braille (1829, in France) (references)

Morse Code (1836) (references)

... . .-.. . -. .. ..- --

Dancing Men (Sir Arthur Conan Doyle, 1903) (references)

Binary Code (1918-1938, probably earlier) (references)

01010011 01100101 01101100 01100101 01101110 01101001 01110101 01101101

HTML Code (1990) (references)

&#83 &#101 &#108 &#101 &#110 &#105 &#117 &#109

ISO 10646 (1991-1993) (references)

0053 0065 006C 0065 006E 0069 0075 006D

British Sign Language (Fingerspelling, BSL; 1992, British Deaf Association Dictionary of British Sign Language) (references)

Encryption (beginner's substitution cypher): (references)

Parts of Speech	Percent	Usage per 100 Million Words	Rank in English
Noun (singular)	97.06%	33	60,273
Noun (proper)	2.94%	1	339,140
Total	100.00%	34	N/A

Expression	Frequency per Day	Expression	Frequency per Day
selenium	612	selenium toner	4
selenium sulfide	38	selenium loudspeaker	4
horn selenium	14	source of selenium	4
oxidant selenium	11	selenium shampoo sulfide	3
vitamin e and selenium	10	food rich selenium	3
information on selenium	9	selenium food source	3
driver horn selenium	8	selenium brazil nut	3
selenium toxicity	8	selenium compound	3
selenium rectifier	8	determination digestion selenium	3
selenium cancer	8	selenium and horse	3
selenium vitamin	7	selenium poisoning	3
selenium sulfide lotion	7	selenium thyroid	3
selenium deficiency	7	the use of selenium	3
selenium speaker	6	cancer colon selenium	3
benefit of selenium	6	selenium yeast	3
fact selenium	5	cancer prostate selenium	3
selenium food	5	acne selenium sulfide	3
74 selenium	5	breast cancer selenium	2
selenium side effects	5	selenium dioxide	2
selenium supplement	4	selenium prostate	2
Source: compiled by the editor from various references; see credits.

Derivations
	Words beginning with "selenium": seleniums. (additional references)
Misspellings
	"Selenium" is suggested in spellcheckers for the following: Asplenium, Elenium, heleniums, Herennium, salonius, Saolanum, Seleni, Selenia, selenuim, Selinous, Selnau, Semenyuk, Sexemium, Silenou, silentio, Silenzio, Silesium, Szelenyi, Zeleni, zeylanicum. (additional references)
Source: compiled by the editor, based on several corpora (additional references).

Expressions using "selenium": selenium acids ♦ selenium cell ♦ Selenium Compounds ♦ Selenium Dioxide ♦ selenium polariser ♦ selenium polarizer ♦ Selenium Radioisotopes ♦ selenium rectifier. Additional references.
Source: compiled by the editor from various references; see credits.

Selenium

Definition: Selenium

Selenium

Noun

Specialty Definitions: Selenium

Specialty Definition: Selenium

Isotopes

Precautions

Selenium and health

Synonym: Selenium

Crosswords: Selenium

Commercial Usage: Selenium

References

Books

Non-Fiction Usage: Selenium

Usage Frequency: Selenium

Expressions: Selenium

Frequency of Internet Keywords: Selenium

Modern Translations: Selenium

Albanian

Arabic

Bulgarian

Chinese

Czech

Danish

Dutch

Finnish

French

German

Greek

Hungarian

Italian

Japanese Kanji

Japanese Katakana

Korean

Pig Latin

Portuguese

Romanian

Russian

Serbo-Croatian

Spanish

Swedish

Turkish

Ukranian

Derivations & Misspellings: Selenium

Derivations

Misspellings

Rhyming with "Selenium"

Anagrams: Selenium

Scrabble® Enable2K-Verified Anagrams

Alternative Orthography: Selenium

53 65 6C 65 6E 69 75 6D

... . .-.. . -. .. ..- --

01010011 01100101 01101100 01100101 01101110 01101001 01110101 01101101

&#83 &#101 &#108 &#101 &#110 &#105 &#117 &#109

0053 0065 006C 0065 006E 0069 0075 006D

5371787180758779

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