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Selenium

Selenium is a chemical element; it has symbol Se and atomic number 34. It has various physical appearances, including a brick-red powder, a vitreous black solid, and a grey metallic-looking form.

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Key facts & relationships

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72Se
synth
74Se
0.860%
75Se
synth
76Se
9.23%
77Se
7.60%
78Se
23.7%

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Overview

Characteristics

Chemical compounds

History

Occurrence

Production

Applications

Pollution

Biological role

Advanced semantic analysis

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Map overview Semantic statistics

Selenium

Nodes264
Edges263
Triples289
Avg. degree1.99
Density0.007576
Components1

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Selenium

Top relations

related to history · 26
Selenium → Alexander Graham Bell, Alexander Marcet, Because, Berzelius, Berzelius's, Both, Earth, Falun Mine, Gahn, Greek, Gripsholm, Hence, However, In, Johan Gottlieb Gahn, Jöns Jacob Berzelius, Marcet, Moon, Pyrite, Selenium's
related to Metal selenides · 17
Selenium → Alkali, Analogous, Cu, Ga, H2S, H2Se, HgSe, HSe, Illustrative, In, It, PbSe, Se2, The, These, With, ZnSe
related to External links · 13
Selenium → Chemical HazardsPeter, Health, Krogt, National Institutes, NIOSH Pocket Guide, Nottingham, SeleniumAssay Archived, SeleniumCDC, The Periodic Table, Toxicological Profile, University, Videos, Wayback MachineATSDR
related to Solar cells · 13
Selenium → Akio Kunioka, As, Charles Fritts, English, Following, However, IBM, In, Only, Recent, Richard Evans Day, Tokio Nakada, William Grylls Adams
related to Toxicity · 13
Selenium → Although, By, Chinese, Elemental, Exceeding, Extreme, Hydrogen, In China, Se, Symptoms, The, This, Tolerable Upper Intake Level
related to Physical properties · 12
Selenium → Black, CS2, In, Other, Se, Se6, Se7, Se8, The, They, Upon, When
related to Organoselenium compounds · 11
Selenium → Consistent, Especially, II, R2Se, R2Se2, Representatives, RSe, RSeH, Se, The, They
is a · 10
Selenium → brittle, chemical element, cofactor for the three thyroid hormone deiodinases, component of the unusual amino acids selenocysteine and selenomethionine, essential micronutrient for animals, essential trace element, rare mineral, semiconductor and is used in photocells, semiconductor showing appreciable photoconductivity, trace element nutrient that functions as cofactor for reduction of antioxidant enzymes
related to Nutritional sources of selenium · 10
Selenium → Allowance, Brazil, Dietary, Drug Administration, FDA, In June, RDA, Selenium-specific, The US Recommended Dietary, US Food
related to Other uses · 9
Selenium → Cadmium, Ionized, Its, LEDs, Se, Sheets, The, X-ray, Zinc

Important terminology Word statistics

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Important terminology

used may sulfur compounds forms copper lead also selenide se form toxic μg element acid plants high found dietary many

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Selenium72Sesynth1.00infobox
Selenium74Se0.860%1.00infobox
Selenium75Sesynth1.00infobox
Selenium76Se9.23%1.00infobox
Selenium77Se7.60%1.00infobox
Selenium78Se23.7%1.00infobox
Selenium79Setrace1.00infobox
Selenium80Se49.8%1.00infobox
Selenium82Se8.82%1.00infobox
SeleniumAppearancegrey metallic-looking, red, and vitreous black (not pictured) allotropes1.00infobox
Seleniumat T (K)5001.00infobox
SeleniumAtomic number (Z)341.00infobox
SeleniumAtomic radiusempirical: 120 pm1.00infobox
SeleniumBlockp-block1.00infobox
SeleniumBoiling point958 K ​(685 °C, ​1265 °F)1.00infobox
SeleniumBrinell hardness736 MPa1.00infobox
SeleniumBulk modulus8.3 GPa1.00infobox
SeleniumCAS Number7782-49-21.00infobox
SeleniumCovalent radius120±4 pm1.00infobox
SeleniumCritical point1766 K, 27.2 MPa1.00infobox
SeleniumCrystal structuregrey: ​hexagonal (hP3)1.00infobox
SeleniumDensity (near r.t.)gray: 4.81 g/cm3 alpha: 4.39 g/cm3 vitreous: 4.28 g/cm31.00infobox
SeleniumDiscovery and first isolationJöns Jakob Berzelius and Johann Gottlieb Gahn (1817)1.00infobox
SeleniumElectron configuration[Ar] 3d10 4s2 4p41.00infobox
SeleniumElectronegativityPauling scale: 2.551.00infobox
SeleniumElectrons per shell2, 8, 18, 61.00infobox
SeleniumGroupgroup 16 (chalcogens)1.00infobox
SeleniumHeat of fusiongray: 6.69 kJ/mol1.00infobox
SeleniumHeat of vaporization95.48 kJ/mol1.00infobox
SeleniumIonization energies1st: 941.0 kJ/mol1.00infobox

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