Scandium

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Scandium, 21Sc
Template:Infobox element/symbol-to-top-image/alt
Scandium
Pronunciation/ˈskændiəm/ (SKAN-dee-əm)
Appearancesilvery white
Standard atomic weight Ar, std(Sc)44.955908(5)[1]
Mass numberSc:
Scandium in the periodic cairt
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 Airn Cobalt Nickel Capper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Siller (element) 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 Gowd Mercur (element) Thallium Leid (element) 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
-

Sc

Y
calciumscandiumtitanium
Atomic nummer (Z)21
Groupgroup 3
Periodperiod 4
Blockd-block
Element category  Transeetion metal
Electron confeeguration[Ar] 3d1 4s2
Electrons per shell2, 8, 9, 2
Pheesical properties
Phase at STPsolit
Meltin pynt1814 K ​(1541 °C, ​2806 °F)
Bylin pynt3109 K ​(2836 °C, ​5136 °F)
Density (near r.t.)2.985 g/cm3
when liquid (at m.p.)2.80 g/cm3
Heat o fusion14.1 kJ/mol
Heat o vapourisation332.7 kJ/mol
Molar heat capacity25.52 J/(mol·K)
Vapour pressur
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 1645 1804 (2006) (2266) (2613) (3101)
Atomic properties
Oxidation states0,[2] +1,[3] +2,[4] +3 (an amphoteric oxide)
ElectronegativityPauling scale: 1.36
Ionisation energies
Atomic radiusempirical: 162 pm
Covalent radius170±7 pm
Van der Waals radius211 pm
Colour lines in a spectral range
Spectral lines o scandium
Ither properties
Naitural occurrenceSc: Primordial
Creestal structurhexagonal close-packed (hcp)
Hexagonal close packed creestal structur for scandium
Thermal expansion(r.t.) (α, poly)
10.2 µm/(m·K)
Thermal conductivity15.8 W/(m·K)
Electrical resistivity(r.t.) (α, poly)
calc. 562 n Ω·m
Magnetic orderinparamagnetic
Young's modulus74.4 GPa
Shear modulus29.1 GPa
Bulk modulus56.6 GPa
Poisson ratio0.279
Brinell haurdness750 MPa
CAS Nummer7440-20-2
History
PredictionDmitri Mendeleev (1871)
DiskiveryLars Fredrik Nilson (1879)
First isolationLars Fredrik Nilson (1879)
Main isotopes o scandium
Iso­tope Abun­dance Hauf-life (t1/2) Decay mode Pro­duct 44m2Sc syn 58.61 h IT 44Sc
γ 44Sc
ε 44Ca
45Sc 100% stable
46Sc syn 83.79 d β 46Ti
γ -
47Sc syn 3.3492 d β 47Ti
γ -
48Sc syn 43.67 h β 48Ti
γ -
| references

Scandium is a chemical element wi seembol Sc an atomic nummer 21. A sillery-white metallic transeetion metal, it haes historically been whiles clessifee'd as a rare yird element, thegither wi yttrium an the lanthanoids. It wis discovered in 1879 bi spectral analysis o the minerals euxenite an gadolinite frae Scandinavie.

Scandium is present in maist o the deposits o rare yird an uranium compoonds, but it is extractit frae thir ores in anly a few mines warldwide. Acause o the law availability an the difficulties in the preparation o metallic scandium, which wis first done in 1937, it teuk till the 1970s afore applications for scandium wur developit. The positive effects o scandium on aluminium alloys wur discovered in the 1970s, an its uise in sic alloys remains its anly major application. The global tred o the pure metal is aroond a hunder poonds a year on average.[5]

The properties o scandium compoonds are intermediate atween thae o aluminium an yttrium. A diagonal relationship exists atween the behaviour o magnesium an scandium, juist as thare is atween beryllium an aluminium. In the chemical compoonds o the elements shawn as group 3, abuin, the predominant oxidation state is +3.

References[eedit | eedit soorce]

  1. Meija, Juris; et al. (2016). "Atomic weights of the elements 2013 (IUPAC Technical Report)". Pure and Applied Chemistry. 88 (3): 265–91. doi:10.1515/pac-2015-0305.
  2. F. Geoffrey N. Cloke; Karl Khan & Robin N. Perutz (1991). "η-Arene complexes of scandium(0) and scandium(II)". J. Chem. Soc., Chem. Commun. (19): 1372–1373. doi:10.1039/C39910001372.
  3. 3.0 3.1 Smith, R. E. (1973). "Diatomic Hydride and Deuteride Spectra of the Second Row Transition Metals". Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences. 332 (1588): 113–127. Bibcode:1973RSPSA.332..113S. doi:10.1098/rspa.1973.0015. Cite error: Invalid <ref> tag; name "Smith" defined multiple times wi different content
  4. 4.0 4.1 McGuire, Joseph C.; Kempter, Charles P. (1960). "Preparation and Properties of Scandium Dihydride". Journal of Chemical Physics. 33 (5): 1584–1585. Bibcode:1960JChPh..33.1584M. doi:10.1063/1.1731452. Cite error: Invalid <ref> tag; name "McGuire" defined multiple times wi different content
  5. Gray, Theodore (2012) The Elements, Black Dog & Leventhal Publishers, p. 57, ISBN 1579128955.

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