మూస:సెలీనియం మూలకము

సెలీనియం, 00Se
సెలీనియం
Pronunciation/sɪˈlniəm/ (-LEE-nee-əm)
Appearanceblack and red allotropes
Standard atomic weight Ar°(Se)
సెలీనియం in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Ununtrium Flerovium Ununpentium Livermorium Ununseptium Ununoctium
S

Se

Te
ఆర్సెనిక్సెలీనియంబ్రోమిన్
Groupమూస:Infobox element/symbol-to-group/format
Periodperiod 4
Block  p-block
Electron configuration[Ar] 3d10 4s2 4p4
Electrons per shell2, 8, 18, 6
Physical properties
Phase at STPsolid
Melting point494 K ​(221 °C, ​430 °F)
Boiling point958 K ​(685 °C, ​1265 °F)
Density (near r.t.)(gray) 4.81 g/cm3
(alpha) 4.39 g/cm3
(vitreous) 4.28 g/cm3
when liquid (at m.p.)3.99 g/cm3
Critical point1766 K, 27.2 MPa
Heat of fusion(gray) 6.69 kJ/mol
Heat of vaporization95.48 kJ/mol
Molar heat capacity25.363 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 500 552 617 704 813 958
Atomic properties
Oxidation states−2, −1, 0,[3] +1,[4] +2, +3, +4, +5, +6 (a strongly acidic oxide)
ElectronegativityPauling scale: 2.55
Atomic radiusempirical: 120 pm
Covalent radius120±4 pm
Van der Waals radius190 pm
Color lines in a spectral range
Spectral lines of సెలీనియం
Other properties
Natural occurrenceprimordial
Crystal structurehexagonal
Hexagonal crystal structure for సెలీనియం
Speed of sound thin rod3350 m/s (at 20 °C)
Thermal expansion(amorphous) 37 µm/(m⋅K) (at 25 °C)
Thermal conductivity(amorphous) 0.519 W/(m⋅K)
Magnetic orderingdiamagnetic[5]
Young's modulus10 GPa
Shear modulus3.7 GPa
Bulk modulus8.3 GPa
Poisson ratio0.33
Mohs hardness2.0
Brinell hardness736 MPa
CAS Number7782-49-2
History
DiscoveryJöns Jakob Berzelius and Johann Gottlieb Gahn (1817)
First isolationJöns Jakob Berzelius and Johann Gottlieb Gahn (1817)
Isotopes of సెలీనియం
Template:infobox సెలీనియం isotopes does not exist
 Category: సెలీనియం
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References

  1. "Standard Atomic Weights: Selenium". CIAAW. 2013.
  2. Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; et al. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry (in ఇంగ్లీష్). doi:10.1515/pac-2019-0603. ISSN 1365-3075.
  3. A Se(0) atom has been identified using DFT in [ReOSe(2-pySe)3]; see Cargnelutti, Roberta; Lang, Ernesto S.; Piquini, Paulo; Abram, Ulrich (2014). "Synthesis and structure of [ReOSe(2-Se-py)3]: A rhenium(V) complex with selenium(0) as a ligand". Inorganic Chemistry Communications. 45: 48–50. doi:10.1016/j.inoche.2014.04.003. ISSN 1387-7003.
  4. Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 0080379419.
  5. Magnetic susceptibility of the elements and inorganic compounds, in Lide, D. R., ed. (2005). CRC Handbook of Chemistry and Physics (86th ed.). Boca Raton (FL): CRC Press. ISBN 0-8493-0486-5.
  6. Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 0080379419.