Cerium

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Cerium,  58Ce
Cerium2.jpg
General properties
Appearance sillery white
Staundart atomic wecht (Ar, staundart) 140.116(1)
Cerium 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 Gold 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
-

Ce

Th
lanthanumceriumpraseodymium
Atomic nummer (Z) 58
Group group n/a
Period period 6
Element category   lanthanide
Block f-block
Electron confeeguration [Xe] 4f1 5d1 6s2[1]
Electrons per shell
2, 8, 18, 19, 9, 2
Pheesical properties
Phase (at STP) solit
Meltin pynt 1068 K ​(795 °C, ​1463 °F)
Bylin pynt 3716 K ​(3443 °C, ​6229 °F)
Density (near r.t.) 6.770 g/cm3
when liquid (at m.p.) 6.55 g/cm3
Heat o fusion 5.46 kJ/mol
Heat o vapourisation 398 kJ/mol
Molar heat capacity 26.94 J/(mol·K)
Vapour pressur
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 1992 2194 2442 2754 3159 3705
Atomic properties
Oxidation states 4, 3, 2, 1
(mildly basic oxide)
Electronegativity Pauling scale: 1.12
Atomic radius empirical: 181.8 pm
Covalent radius 204±9 pm
Color lines in a spectral range
Miscellanea
Crestal structur face-centred cubic (fcc)
Face-centered cubic creestal structur for cerium
Speed o soond thin rod 2100 m/s (at 20 °C)
Thermal expansion (r.t.) (γ, poly) 6.3 µm/(m·K)
Thermal conductivity 11.3 W/(m·K)
Electrical resistivity (r.t.) (β, poly) 828 n Ω·m
Magnetic orderin paramagnetic[2]
Young's modulus (γ form) 33.6 GPa
Shear modulus (γ form) 13.5 GPa
Bouk modulus (γ form) 21.5 GPa
Poisson ratio (γ form) 0.24
Mohs haurdness 2.5
Vickers haurdness 270 MPa
Brinell haurdness 412 MPa
CAS Nummer 7440-45-1
History
Namin efter dwarf planet Ceres, itsel named efter Roman deity o agricultur Ceres
Diskivery Martin Heinrich Klaproth, Jöns Jakob Berzelius, Wilhelm Hisinger (1803)
First isolation Carl Gustaf Mosander (1839)
Main isotopes o cerium
Iso­tope Abun­dance Hauf-life (t1/2) Decay mode Pro­duct
134Ce syn 3.16 d ε 134La
136Ce 0.185% >3.8×1016 y (β+β+) 136Ba
138Ce 0.251% >1.5×1014 y (β+β+) 138Ba
139Ce syn 137.640 d ε 139La
140Ce 88.450% - (SF)
141Ce syn 32.501 d β 141Pr
142Ce 11.114% >5×1016 y (ββ) 1.417 142Nd
(α) 1.298 138Ba
144Ce syn 284.893 d β 144Pr
Decay modes in parentheses is predict, but hisna yet been observed
| references | in Wikidata

Cerium is a chemical element wi seembol Ce an atomic nummer 58. It is a saft, silvery, ductile metal which easily oxidizes in air. Cerium wis named efter the dwarf planet Ceres (itsel named for the Roman goddess o agricultur). Cerium is the maist abundant o the rare yird elements, makin up aboot 0.0046% o the Yird's crust bi wicht. It is foond in a feck o minerals, the maist important bein monazite an bastnasite. Thare a wheen o ommercial applications o cerium. Thay include catalysts, additives fur tae fuel tae reduce emissions an tae glass an enamels tae chynge thair colour. Cerium oxide is an important component o gless polishin pouders an phosphors uised in screens an fluorescent lamps. It is uised in the "flint" (actually ferrocerium) o lichters.

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