Skip to main content

Allgemein

Written by Sabrina Heimrich on . Posted in Allgemein.

Europium

EU • Atomic Number 63

Europium

Europium is a silvery, lustrous heavy metal and is classified among the middle rare earth elements.

Its most important property by far is its ability to emit light in very specific, pure, and intense colors. As a result, the primary application of europium is in the production of phosphors for display and lighting technologies.

In 1890, Paul Émile Lecoq de Boisbaudran discovered unknown spectral lines in a samarium–gadolinium concentrate. The discovery of europium is credited to Eugène-Anatole Demarçay, who in 1896 suspected the presence of another element within the recently discovered samarium. In 1901, he succeeded in isolating europium. Metallic europium was not produced until several years later.

  • Occurence

    Europium is a rare element on Earth, with an average abundance of about 2 ppm in the continental crust.

    It occurs as a minor constituent in various lanthanide-bearing minerals. Europium is found in monazite, bastnäsite, and xenotime.

    In some igneous rocks, the concentration of europium is either higher or lower than expected based on the relative abundance pattern of rare earth elements normalized to chondrites. This phenomenon is known as the europium anomaly and is caused by the fact that under reducing conditions in magma, Eu³⁺ can be reduced to Eu²⁺.


  • Extraction

    After breaking down the raw materials, such as monazite or bastnäsite, using sulfuric acid or sodium hydroxide, various separation methods can be applied.

    In addition to ion exchange, a process based on liquid–liquid extraction and the reduction of Eu³⁺ to Eu²⁺ is commonly used. When bastnäsite is the starting material, cerium is first removed as cerium(IV) oxide, and the remaining rare earth elements are dissolved in hydrochloric acid. A mixture of DEHPA (di(2-ethylhexyl)phosphoric acid) and kerosene is then used in liquid–liquid extraction to separate europium, gadolinium, and samarium from the other rare earth elements. These three are further separated by selectively reducing europium to Eu²⁺ and precipitating it as poorly soluble europium(II) sulfate, while the other ions remain in solution.

    Metallic europium can be produced by reacting europium(III) oxide with lanthanum or mischmetal. When this reaction is carried out under vacuum, europium distills off and can thus be separated from other metals and impurities.

  • Application

    The first major technical application of europium was the production of europium-doped yttrium vanadate. This red phosphor, discovered in 1964 by Albert K. Levine and Frank C. Palilla, soon played a key role in the development of color television. As a result, the first rare earth mine, operating since 1954 in Mountain Pass, California, was significantly expanded to meet demand.

    Europium continues to be used as a dopant in the production of phosphors for aircraft instrument displays and compact fluorescent lamps (CFLs). Phosphors containing both divalent and trivalent europium are used for different colors.

    For red phosphors, europium-doped yttrium oxide (Y₂O₃:Eu³⁺) is primarily used. Previously, yttrium oxysulfide and the first significant red phosphor, yttrium vanadate:Eu³⁺, were also used. Eu²⁺ is typically used as a blue phosphor in compounds like strontium chlorophosphate (Sr₅(PO₄)₃Cl:Eu²⁺, also known as strontium chloroapatite, SCAP) and barium magnesium aluminate (BaMgAl₁₁O₁₇:Eu²⁺, BAM).

    Plasma displays require phosphors that convert VUV radiation emitted by the noble gas plasma into visible light. Europium-doped phosphors are used here for both the blue and red parts of the spectrum — BAM for blue, and (Y,Gd)BO₃:Eu³⁺ for red.

    In mercury high-pressure lamps, such as those used in street lighting, europium-doped yttrium vanadate is applied to the glass to make the light appear whiter and more natural.

    Due to its ability to absorb neutrons, europium can also be used in control rods for nuclear reactors. Europium-containing control rods have been tested in various Soviet experimental reactors such as BOR-60 and BN-600.

    As europium hexaboride, it is also used as a coating for oxide cathodes in thermionic emission applications.

    Europium fluorescence is used as an anti-counterfeiting feature in euro banknotes.

    This fluorescence property is also useful in fluorescence spectroscopy. Europium can be bound in specific complexes that selectively react and accumulate at desired locations, such as with certain proteins.

    Soluble europium compounds are mildly toxic.

     
    1. Europium(III)-doped yttrium oxysulfide (Y₂O₂S:Eu³⁺) forms the red phosphor used in color CRTs (cathode ray tubes).
    2. Europium(II)-doped barium fluorobromide (BaFBr:Eu²⁺) is used in photostimulated luminescence (PSL) detectors.
    3. Eu³⁺-doped solids usually show red luminescence, while Eu²⁺ can emit across the entire optical spectrum (from UV to red), depending on the host lattice.
    4. Europium is used as a dopant in phosphors for light sources such as high-pressure mercury lamps and energy-saving lamps.
    5. Dopant in scintillation crystals (as an activator).
    6. Organic europium compounds are used as shift reagents in NMR spectroscopy.
    7. Europium-tetracycline complexes are used in fluorescence spectroscopy to detect hydrogen peroxide.
    8. TRFIA (time-resolved fluoroimmunoassay): Eu³⁺ ions fluoresce only briefly in water. Chelating agents are used to create a hydrophobic environment around Eu³⁺ ions, extending fluorescence duration. This makes it possible to distinguish europium fluorescence from other short-lived background signals in complex organic mixtures.

  • Unique Properties

    As a base metal, europium is one of the most reactive rare earth elements. When exposed to air, the silvery, shiny metal tarnishes immediately. At temperatures above 150 °C, it ignites and burns with a red flame to form the sesquioxide Eu₂O₃. In water, it reacts with the evolution of hydrogen to form the hydroxide.

    Europium reacts with the halogens fluorine, chlorine, bromine, and iodine to form the respective trihalides. When reacting with hydrogen, non-stoichiometric hydride phases are formed, with hydrogen occupying the interstitial spaces of the metal’s crystal lattice.

    Europium dissolves slowly in water but rapidly in acids, producing hydrogen gas and the colorless Eu³⁺ ion. The also colorless Eu²⁺ ion can be obtained via electrolytic reduction at the cathode in aqueous solution. It is the only divalent lanthanoid ion that is stable in aqueous solution. Europium also dissolves in liquid ammonia, forming a deep blue solution similar to alkali metals, in which solvated electrons are present.

    The Eu³⁺ cation, like Sm³⁺, Tb³⁺, and Dy³⁺, can emit visible light when coordinated in a suitable complex and excited at specific wavelengths. While Eu³⁺ is colorless in aqueous solution, coordination with organic ligands possessing extended π-electron systems greatly enhances its luminescent properties via the antenna effect. The π-electrons of the ligand absorb incoming light (approx. 355 nm) and transfer the energy to the 5d electrons of Eu³⁺, which are then excited to the 4f orbitals. When these electrons return to their ground state, visible light (approx. 610 nm) is emitted.

    With a density of 5.245 g/cm³, europium has an unusually low density — significantly lower than that of neighboring lanthanoids such as samarium or gadolinium, and even lower than lanthanum.

    This also applies to its comparatively low melting point (826 °C) and boiling point (1440 °C), in contrast to the typical trend among the lanthanoids (e.g., gadolinium melts at 1312 °C and boils at 3000 °C). These anomalies contradict the lanthanoid contraction and are attributed to europium’s electron configuration. Because its 4f shell is half-filled, only two valence electrons are available for metallic bonding, resulting in weaker bonding forces and a significantly larger atomic radius — a phenomenon also observed in ytterbium.

    Under normal conditions, europium crystallizes in a body-centered cubic (bcc) structure with a lattice parameter of a = 455 pm. Two additional high-pressure phases are known. Unlike other lanthanoids, europium (similar to ytterbium) does not exhibit a double-hexagonal or samarium-type structure. The first phase transition occurs at 12.5 GPa, above which europium crystallizes in a hexagonal close-packed (hcp) structure with lattice parameters a = 241 pm and c = 545 pm. At pressures above 18 GPa, a third phase (Eu-III), similar to the hcp arrangement, has been identified.

    At pressures of at least 34 GPa, europium’s oxidation state in the metal changes from divalent to trivalent. This allows the element to become superconducting at approximately 80 GPa and 1.8 K.

    Europium ions embedded in suitable host lattices show pronounced fluorescence. The emitted wavelength depends on the oxidation state. Eu³⁺ fluoresces intensely red, largely independent of the host lattice, emitting between 613 and 618 nm. In contrast, Eu²⁺ fluorescence is more sensitive to the host material. For example, emission occurs at 447 nm (blue) in barium magnesium aluminate (BaMgAl₁₁O₁₇:Eu²⁺), and at 520 nm (green) in strontium aluminate (SrAl₂O₄:Eu²⁺).

    While ¹⁵³Eu is stable, evidence suggests that ¹⁵¹Eu is an alpha emitter. The lower limit of its half-life is estimated at 1.7 trillion years. Europium and its compounds are considered toxic. Metal dusts are both flammable and explosive hazards.

Europium, Eu, rare earth element, lanthanide, phosphors, fluorescent materials, europium uses, TV and display phosphors, nuclear control rods, rare earth metals, ISE AG metals, ISE AG

Read more …Europium

  • Hits: 468

Written by Sabrina Heimrich on . Posted in Allgemein.

Erbium

Er • Atomic Number 68

Erbium

Erbium is a silvery-white metal that belongs to the heavy rare earth elements. It is malleable but also quite brittle.

The name is derived from the Ytterby mine near Stockholm.

Erbium was discovered in 1843 by Carl Gustav Mosander. However, the supposedly pure oxide was actually a mixture of oxides of erbium, scandium, holmium, thulium, and ytterbium.

The clarification of this mixture was later achieved by chemists Marc Delafontaine and Per Teodor Cleve. Pure erbium oxide was first produced in 1905 by the French chemist Georges Urbain and the American chemist Charles James.

Erbium Oxide

  • Occurrence

    As a heavy rare earth element (HREE), erbium is more commonly found in HREE-enriched minerals such as xenotime and euxenite. Additionally, erbium occurs in ion-adsorption clays (clay deposits), which, due to their relatively simple processing despite the low percentage of rare earth elements, represent the most important source of HREEs. The primary sources are ion-adsorption clay minerals from southern China (Jiangxi and Guangdong provinces) and Myanmar.

  • Extraction

    After an elaborate separation of other erbium-associated elements, the oxide is converted with hydrofluoric acid into erbium fluoride. It is then reduced to metallic erbium using calcium, producing calcium fluoride as a byproduct. Remaining calcium residues and impurities are removed through an additional vacuum remelting process.

  • Application

    Its unique interaction with light accounts for most of the element’s applications. Unlike cerium or lanthanum, its uses are more specialized but absolutely crucial for modern technologies.

    In fiber optic networks, erbium-doped glasses serve as optical amplifiers. These erbium-doped fiber amplifiers (EDFAs) form the backbone of the global internet. They enable data transmission over thousands of kilometers under the oceans without the need for electrical signal regeneration along the way.

    In medicine, erbium lasers (Er:YAG lasers — erbium-doped yttrium aluminum garnet) are used in dermatology and dentistry due to their precise and controlled effects.

    Besides medical lasers, erbium is also used in other high-precision lasers: erbium-doped crystals (such as Er:YAG, Er:YSGG) are employed in lasers for precise cutting, welding, and marking in industrial applications.

    Erbium oxide, which has a beautiful and distinctive pink to rose color, is used as a dye for glass, jewelry, and sunglasses.

    (Er₂O₃) exhibits a very attractive and characteristic pink to rose hue.

    Besides its optical properties, erbium is useful in nuclear power due to its ability to easily absorb free neutrons. This makes it suitable for use in control rods in nuclear reactors.

    Furthermore, erbium alloys are used in cryocoolers for applications at liquid helium temperatures because of their high specific heat capacity.

    Fiber Optics Using Erbium

    General Information
    Name, Symbol, Atomic Number Erbium, Er, 68
    Series Lanthanoid
    Group, Period, Block La, 6, f
    Appearance silvery-white
    CAS-Number 7440-52-0
    Abundance in Earth's crust 2.3 ppm
    Atomic Properties
    Atomic Mass 167.26 u
    Atomic Radius 175 pm
    Covalent Radius 189 pm
    Electron Configuration [Xe] 4f¹² 6s²
    1. Ionization Energy 589.3 kJ/mol
    2. Ionization Energy 1150 kJ/mol
    3. Ionization Energy 2194 kJ/mol
    4. Ionization Energy -
    Physical Properties
    State of Matter solid
    Crystal Structure Hexagonal
    Density 9.045 g/cm³ (at 25 °C)
    Magnetism

    Paramagnetic (χm = 1.4 × 10⁻³)
    Melting Point 1802 K (1529 °C)
    Boiling Point 3141 K (2868 °C)
    Molar Volume 18.46 * 10⁻⁶ m³/mol
    Heat of Vaporization 285 kJ/mol
    Heat of Fusion 19.9 kJ/mol
    Electrical Conductivity 1.16 * 10⁶ A/(V·m)
    Thermal Conductivity 15 W/(m*K)

Erbium, Er, rare earth element, lanthanide, heavy rare earth, silvery-white metal, malleable metal, optical amplifiers, fiber optics, lasers, nuclear applications, ISE AG metals, ISE AG

Read more …Erbium

  • Hits: 524

Written by Sabrina Heimrich on . Posted in Allgemein.

Dysprosium

Dy • Atomic Number 66

Dysprosium

Dysprosium is a silvery-gray, malleable and ductile metal that belongs to the heavy rare earth elements.

It is highly reactive. Together with holmium, dysprosium has the highest magnetic moment (10.6 μB) of all naturally occurring chemical elements.

The discovery of dysprosium traces back to studies of gadolinite (then still called ytterbite), a mineral from the Ytterby mine near Stockholm, Sweden.

In 1879, Per Theodor Cleve and Jacques-Louis Soret independently discovered through spectroscopic investigations that erbium contained additional elements. Following Cleve’s suggestion, these were named holmium and thulium.

In 1886, Paul Émile Lecoq de Boisbaudran conducted fractionation experiments on holmium and realized that another element must exist. Since the unknown element was experimentally very difficult to isolate and he was unable to obtain a pure fraction, he named it dysprosium, meaning “the inaccessible.”

In 1906, Georges Urbain succeeded in producing pure dysprosium oxide for the first time. In 1936, Wilhelm Klemm and Heinrich Bommer isolated metallic dysprosium for the first time. In 1950, Frank Harold Spedding developed an effective ion-exchange separation method for dysprosium and yttrium.

  • Occurrence

    The occurrence of dysprosium in the continental Earth’s crust is about 5.2 ppm. In terms of abundance, it ranks behind most of the light rare earth elements such as cerium, neodymium, and samarium, but ahead of most heavy rare earths like erbium, ytterbium, and holmium.

    Minerals with particularly high dysprosium content include xenotime and gadolinite-(Y). In contrast, ores important for extracting other lanthanides, such as monazite and bastnäsite, contain only small amounts of dysprosium.

    The main sources of dysprosium are ion-adsorption clay minerals (clay deposits) found in southern China (Jiangxi and Guangdong provinces) and Myanmar.

    In these clay deposits, the rare earth elements are not part of a crystal structure but are adsorbed as ions onto clay particles. This allows for their extraction via ion-exchange processes, which are especially simple and cost-effective. Crucially, these deposits are highly enriched with valuable heavy rare earth elements like dysprosium and terbium.

  • Extraction

    After an elaborate separation of other dysprosium-associated elements, the oxide is converted with hydrofluoric acid to dysprosium fluoride. It is then reduced with calcium to metallic dysprosium, producing calcium fluoride as a byproduct. Remaining calcium residues and impurities are removed through an additional vacuum remelting process. High-purity dysprosium is obtained after vacuum distillation.

    Commercial separation is performed by liquid-liquid extraction or ion-exchange methods. The metal is produced by metallothermic reduction of the anhydrous halides using alkali or alkaline earth metals. Further purification of the metal is achieved by vacuum distillation.

    Dysprosium exists in three allotropes (structural forms). The α-phase is hexagonally close-packed (HCP) with lattice parameters a = 3.5915 Å and c = 5.6501 Å at room temperature. Upon cooling to approximately 90 K (-183 °C / -297 °F), the ferromagnetic order is accompanied by an orthorhombic distortion of the HCP lattice. The β-phase has lattice parameters a = 3.595 Å, b = 6.184 Å, and c = 5.678 Å at 86 K (-187 °C / -305 °F). The γ-phase is body-centered cubic (BCC) with a = 4.03 Å at 1381 °C (2518 °F).

  • Application

    The main applications of dysprosium are as alloying additions to Nd₂Fe₁₄B permanent magnet materials (where part of the neodymium is replaced by dysprosium) to increase both the Curie temperature and especially the coercive field strength, thereby improving the high-temperature performance of the alloy. The metal is also a component of the magnetostrictive material Terfenol D (Tb₀.₃Dy₀.₇Fe₂).

    Due to its relatively high neutron absorption cross-section, dysprosium is used in control rods for nuclear reactors. Its compounds have been employed in the production of laser materials and phosphor activators, as well as in halogen metal vapor lamps.

    The economic and technical significance of dysprosium is relatively low. Its annual production is estimated at less than 100 tons. It is used in various alloys, specialty magnets, and, alloyed with lead, as shielding material in nuclear reactors. However, its use in magnets for wind turbines has contributed to making rare earth metals a scarce resource. Additionally, the world’s largest supplier, China, restricts exports to increase domestic value creation.

    Dysprosium oxide — Chemically, dysprosium behaves like a typical trivalent rare earth element and forms a series of pale yellow compounds in the +3 oxidation state.

Dysprosium, Dy, rare earth element, lanthanide, high-temperature magnets, permanent magnets, magnet alloys, wind turbines, electric vehicles, rare earth metals, element 66, ISE AG metals, strategic metal, ISE AG

Read more …Dysprosium

  • Hits: 515

Written by Sabrina Heimrich on . Posted in Allgemein.

Cerium

Cerium • Ce • Atomic Number 58

Cerium

Cerium is a silvery-gray, relatively soft, ductile, paramagnetic, and reactive metal. It is the most abundant lanthanide and occurs about as frequently as copper. Cerium belongs to the group of light rare earth elements.

In 1803, Swedish chemists Jöns Jacob Berzelius and Wilhelm Hisinger discovered the element. Independently, it was also discovered around the same time by German chemist Martin Klaproth. It was named after the dwarf planet Ceres, which had been discovered shortly before.

Like most rare earth elements, cerium was first identified in the form of its oxide — cerium dioxide (cerium(IV) oxide) — and only decades later isolated as a pure metal.

In the second half of the 19th century, Carl Auer von Welsbach successfully developed two products that required the use of cerium: gas mantles and ferrocerium (lighter flints). Auer's gas mantles enabled gas lamps to emit a bright, white light.

As with other rare earth elements, cerium is never found in its pure form in nature. It is extracted from minerals such as xenotime, monazite, and bastnäsite, or from ion-adsorption clays.

  • Occurrence

    Cerium is primarily extracted from cerium-containing monazite and bastnäsite. It also occurs in allanite, zircon, samarskite, and the titanium mineral perovskite. Major producers include the United States, China, Russia, Australia, and India.

    In nature, four stable or extremely long-lived isotopes of cerium occur: stable cerium-140 (88,48 percent) and radioactive cerium-142 (11.08 percent), as well as cerium-138 (0,25 percent) and cerium-136 (0,19 percent). Excluding nuclear isomers, a total of 38 radioactive isotopes of cerium have been identified. Their mass numbers range from 119 to 157, with half-lives varying from just 1,02 seconds for cerium-151 to 5 × 10¹⁶ years for cerium-142.

    Cer-oxide

  • Extraction

    Cerium metal is produced by electrolysis and metallothermic reduction of its halides using alkali or alkaline earth metals. It exists in four allotropic (structural) forms. The α-phase is face-centered cubic (FCC) with a = 4.85 Å at 77 K (−196 °C or −321 °F). The β-phase forms just below room temperature and is double hexagonally close-packed (DHCP) with a = 3.6810 Å and c = 11.857 Å. The γ-phase is the room temperature form and is face-centered cubic (FCC) with a = 5.1610 Å at 24 °C (75 °F). The δ-phase is body-centered cubic (BCC) with a = 4,12 Å at 757 °C (1,395 °F).

    After an elaborate separation of accompanying rare earth elements, cerium oxide is converted into cerium fluoride using hydrofluoric acid. It is then reduced to metallic cerium by calcium, forming calcium fluoride as a by-product. Remaining calcium and other impurities are removed in an additional vacuum remelting step.

  • Application

    Although rare earth elements are classified as critical raw materials, scarcity does not apply to all of them. As previously mentioned, cerium is the most abundant of the rare earth elements. Since rare earths always occur together in deposits and are extracted collectively, this leads to significant and ongoing overproduction of cerium (and lanthanum, the second most abundant rare earth element).

    Despite the demand for cerium and lanthanum, it is nowhere near sufficient to absorb the massive supply generated through mining.

    Cerium's ability to switch between the oxidation states Ce³⁺ and Ce⁴⁺ makes it especially useful in catalytic and redox-active processes. Its largest application is in automotive exhaust catalysts. In three-way catalytic converters, cerium oxide is a key component. Another major application is in fluid catalytic cracking (FCC) catalysts used in oil refineries.

    Cerium oxide (CeO₂) is also an excellent polishing agent for glass, lenses, and silicon wafers.

    In the glass and ceramics industries, cerium is added to glass and glazes to achieve specific properties—such as decolorization by removing impurities in glass and ceramic glazes. This results in clearer glass and purer ceramic finishes. Cerium can also impart a yellow tint to glass, which is used as a UV protection feature.

    Cerium continues to be used in lighting applications. In energy-saving lamps, it enhances light quality in fluorescent phosphors. In white LEDs, cerium-doped phosphors (e.g., YAG:Ce) are a key component.

    When added in small amounts to aluminum or magnesium alloys, cerium improves their corrosion resistance and mechanical properties.

    Cerium-based coatings and conversion layers (e.g., on aluminum or steel) offer excellent corrosion protection and are being researched as more environmentally friendly alternatives to chromate-based coatings.

    Cerium dioxide–based materials are used as electrolytes in solid oxide fuel cells (SOFCs) due to their ionic conductivity.

    Cerium-rich alloys (e.g., with cobalt or iron) can absorb and release hydrogen and are being studied for hydrogen storage technologies.

    Cerium is still used today in lighter flints—a commercial application that dates back to the 19th century, introduced by the enterprising chemist Carl Auer von Welsbach.

  • Unique Properties

    The silvery-white, lustrous metal is the second most reactive lanthanide after europium. Superficial damage to its protective yellow oxide layer can ignite the metal. Above 150 °C, it burns with intense glowing to form cerium dioxide. It reacts with water to produce cerium hydroxide.

    Cerium occurs in compounds as a trivalent, colorless cation or as a tetravalent, yellow to orange-colored cation.

    When exposed to heat, cerium is strongly attacked by ethanol and water. It is also heavily corroded in alkaline solutions, forming cerium hydroxides. In acids, it dissolves to form salts. Because the chemical properties of the rare earth elements are similar, metallic cerium is rarely used in pure form; instead, it is typically employed as part of the mixture obtained during the extraction from rare earth minerals, known as mischmetal.

    Like all lanthanides, cerium is slightly toxic. Metallic cerium can ignite at temperatures as low as 65 °C. When finely divided, it can heat up in air without an external energy source and eventually ignite. Its ignition tendency strongly depends on particle size and distribution. Cerium fires must not be extinguished with water, as explosive hydrogen gas would be produced.

    Along with praseodymium and terbium, cerium is distinguished from other rare earths by forming compounds in which it exhibits the +4 oxidation state. In solution, it is even the only rare earth element to show a +4 oxidation state. Salts of the Ce⁴⁺ ion (core salts), which are powerful yet stable oxidizing agents, are used in analytical chemistry to determine oxidizable substances such as iron (iron in the +2 oxidation state). Cerium in the +3 oxidation state behaves like a typical rare earth element.

    General Information
    Name, Symbol, Atomic Number Cer, CE, 58
    Series Lanthanides
    Groupe, Periode, Block La, 6, f
    Appearance silvery-white
    CAS-Number 7440-45-1
    Mass Fraction in the Earth's Crust 43ppm
    Atomic Properties
    Atomic Mass 140,116 u
    Atomic Radius 185 pm
    Covalent Radius 204 pm
    Electron Configuration [Xe] 4f 1 5d 1 6s 2
    1. Ionization Energy 5,5386(4) eV ≈ 534 KJ/mol
    2. Ionization Energy 10,956(20) eV ≈ 1057 KJ/mol
    3. Ionization Energy 20,1974(25) eV ≈ 1949 KJ/mol
    4. Ionization Energy 36,906(9) eV ≈ 3561 KJ/mol
    5. Ionization Energy 65,55(25) eV ≈ 6320 kJ/mol
    Physical Properties
    State of Matter solid
    Crystal Structure Face-Centered Cubic
    Density 6,773 g/cm3 (25 °C)
    Mohs Hardness 2,5
    Magnetism

    paramagnetic (χm = 1,4 * 10−3)
    Melting Point 1068 K (795 °C)
    Boiling Point 3743 K (3470 °C)
    Molar Volume 20,69 * 10-6 m3/mol
    Heat of Vaporization 398 KJ/mol
    Heat of Fusion 5,5 KJ/mol
    Speed of Sound 2100 m/s bei 293,15 K
    Electrical Conductivity 1,35 * 106 S/m
    Thermal Conductivity 11 W/(m*K)

Cerium, Ce, rare earth element, lanthanide, silvery-white metal, industrial uses, catalysts, glass polishing, mischmetal, rare earth metals, element 58, ISE AG metals, ISE AG

Read more …Cerium

  • Hits: 606