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67 dysprosium ← holmium → erbium
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↑
Ho
↓
Es
General
Name, Symbol, Number holmium, Ho, 67
Chemical series lanthanides
Group, Period, Block n/a, 6, f
Appearance silvery white
Standard atomic weight 164.93032(2)  g·mol−1
Electron configuration [Xe] 4f11 6s2
Electrons per shell 2, 8, 18, 29, 8, 2
Physical properties
Phase solid
Density (near r.t.) 8. Erbium (ˈɝbiəm is a Chemical element with the symbol Er and Atomic number 68 Einsteinium (aɪnˈstaɪniəm is a Metallic Synthetic element. This is a typical display of the periodic table of the elements and contains the symbol and Atomic number of each element Wikipedia talkFeatured lists for an explanation of this and other inclusion tags below -->This is a list of Chemical elements, sorted by name Wikipedia talkFeatured lists for an explanation of this and other inclusion tags below -->This is a list of chemical elements by symbol, including the A table of Chemical elements ordered by Atomic number and color coded according to type of element In Chemistry a group, also known as a family, is a vertical column in the Periodic table of the Chemical elements There are 18 groups in Terminology The Trivial name " Rare earths " is sometimes used to describe all the lanthanoids together with Scandium and Yttrium In Chemistry a group, also known as a family, is a vertical column in the Periodic table of the Chemical elements There are 18 groups in In the Periodic table of the elements, a period is a horizontal row of the table A block of the Periodic table of elements is a set of adjacent groups The respective highest-energy electrons in each element in a block belong to the same Atomic Occurrence Scandium yttrium and the Lanthanides (except promethium tend to occur together in the Earth's crust and are relatively abundant compared with most D-block A period 6 element is one of the Chemical elements in the sixth row (or period) of the periodic table of the elements, including the Lanthanides The f-block of the Periodic table of the elements consists of those elements (sometimes referred to as the inner transition elements) for which in the The atomic mass (ma is the Mass of an atom most often expressed in unified atomic mass units The atomic mass may be considered to be the total mass To help compare different orders of magnitude, the following list describes various Mass levels between 10&minus36&thinsp kg and 1053&thinspkg In Atomic physics and Quantum chemistry, electron configuration is the arrangement of Electrons in an Atom, Molecule, or other Xenon (ˈzɛnɒn or) is a Chemical element represented by the symbol Xe. The electron is a fundamental Subatomic particle that was identified and assigned the negative charge in 1897 by J An electron shell may be crudely thought of as an Orbit followed by Electrons around an Atom nucleus. In the Physical sciences a phase is a Set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties A solid' object is in the States of matter characterized by resistance to Deformation and changes of Volume. The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different Room temperature (also referred to as ambient temperature) is a common term to denote a certain Temperature within enclosed space at which humans are accustomed 79  g·cm−3
Liquid density at m.p. 8. The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different The melting point of a solid is the temperature range at which it changes state from solid to Liquid. 34  g·cm−3
Melting point 1734 K
(1461 °C, 2662 °F)
Boiling point 2993 K
(2720 °C, 4928 °F)
Heat of fusion 17. The melting point of a solid is the temperature range at which it changes state from solid to Liquid. The kelvin (symbol K) is a unit increment of Temperature and is one of the seven SI base units The Kelvin scale is a thermodynamic The Celsius Temperature scale was previously known as the centigrade scale. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 The boiling point of a liquid is the temperature at which the Vapor pressure of the liquid equals the environmental pressure surrounding the liquid The kelvin (symbol K) is a unit increment of Temperature and is one of the seven SI base units The Kelvin scale is a thermodynamic The Celsius Temperature scale was previously known as the centigrade scale. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 The standard Enthalpy of fusion (symbol \Delta{}H_{fus} also known as the heat of fusion or specific melting heat, is the amount of 0  kJ·mol−1
Heat of vaporization 265  kJ·mol−1
Specific heat capacity (25 °C) 27. The joule per mole (symbol J·mol-1 is an SI derived unit of energy per amount of material The enthalpy of vaporization, (symbol \Delta{}_{v}H also known as the heat of vaporization or heat of evaporation, is the Energy required The joule per mole (symbol J·mol-1 is an SI derived unit of energy per amount of material Specific heat capacity, also known simply as specific heat, is the measure of the heat energy required to increase the Temperature of a unit quantity 15  J·mol−1·K−1
Vapor pressure
P(Pa) 1 10 100 1 k 10 k 100 k
at T(K) 1432 1584 (1775) (2040) (2410) (2964)
Atomic properties
Crystal structure hexagonal
Oxidation states 3
(basic oxide)
Electronegativity 1. Vapor pressure (also known as equilibrium vapor pressure or saturation vapor pressure) is the Pressure of a Vapor in equilibrium In Mineralogy and Crystallography, a crystal structure is a unique arrangement of Atoms in a Crystal. In Chemistry, the oxidation state is an indicator of the degree of Oxidation of an Atom in a Chemical compound. In Chemistry, a base is most commonly thought of as an aqueous substance that can accept Protons This refers to the Brønsted-Lowry theory of acids and " Electronegativity " is the opposite of " Electropositivity," which describes an element's ability to donate electrons 23 (Pauling scale)
Ionization energies
(more)		 1st:  581. The ionization potential, ionization energy or EI of an Atom or Molecule is the Energy required to remove an Electron These tables list the Ionization energy in kJ/mol necessary to remove one mole of Electrons from one mole of neutral gaseous Atoms (first energy respectively 0  kJ·mol−1
2nd:  1140  kJ·mol−1
3rd:  2204  kJ·mol−1
Atomic radius 175  pm
Miscellaneous
Magnetic ordering paramagnetic
Electrical resistivity (r.t.) (poly) 814 nΩ·m
Thermal conductivity (300 K) 16. The joule per mole (symbol J·mol-1 is an SI derived unit of energy per amount of material Atomic radius, and more generally the size of an atom, is not a precisely defined Physical quantity, nor is it constant in all circumstances A picometre ( American spelling: picometer, symbol pm) is a unit of Length in the Metric system, equal to one trillionth In Physics, magnetism is one of the Phenomena by which Materials exert attractive or repulsive Forces on other Materials. Paramagnetism is a form of magnetism which occurs only in the presence of an externally applied magnetic field Electrical resistivity (also known as specific electrical resistance) is a measure of how strongly a material opposes the flow of Electric current. Room temperature (also referred to as ambient temperature) is a common term to denote a certain Temperature within enclosed space at which humans are accustomed In Physics, thermal conductivity, k is the property of a material that indicates its ability to conduct Heat. 2  W·m−1·K−1
Thermal expansion (r.t.) (poly)
11. When the Temperature of a substance changes the energy that is stored in the Intermolecular bonds between atoms changes Room temperature (also referred to as ambient temperature) is a common term to denote a certain Temperature within enclosed space at which humans are accustomed 2 µm/(m·K)
Speed of sound (thin rod) (20 °C) 2760 m/s
Young's modulus 64. Sound is a vibration that travels through an elastic medium as a Wave. In Solid mechanics, Young's modulus (E is a measure of the Stiffness of an isotropic elastic material 8  GPa
Shear modulus 26. In Materials science, shear modulus or modulus of rigidity, denoted by G, or sometimes S or μ, is defined as the ratio of Shear 3  GPa
Bulk modulus 40. 2  GPa
Poisson ratio 0. Poisson's ratio ( ν) named after Simeon Poisson, is the ratio of the relative contraction strain, or transverse strain (normal to 231
Vickers hardness 481  MPa
Brinell hardness 746  MPa
CAS registry number 7440-60-0
Selected isotopes
Main article: Isotopes of holmium
iso NA half-life DM DE (MeV) DP
163Ho syn 4570 yr ε 0. The Vickers hardness test was developed in 1924 by Smith and Sandland as an alternative method to measure the Hardness of materials The Brinell scale characterizes the indentation Hardness of materials through the scale of penetration of an indenter loaded on a material test-piece CAS registry numbers are unique numerical identifiers for Chemical compounds Polymers biological sequences mixtures and Alloys They are also referred to Natural Holmium ( Ho) contains one Stable Isotope, holmium 165 Isotopes (Greek isos = "equal" tópos = "site place" are any of the different types of atoms ( Nuclides In Chemistry, natural abundance (NA refers to the abundance Isotopes of a Chemical element as naturally found on a planet Half-Life (computer-game page here It's already listed in the disambiguation page Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. The decay energy is the Energy released by a Nuclear decay. The energy difference of the Reactants is often written as Q: where Q In Nuclear physics, a decay product, also known as a daughter product, daughter isotope or daughter nuclide, is a Nuclide A synthetic radioisotope is a Radionuclide that is not found in nature no natural process or mechanism exists which produces it or it is so unstable that it decays away in Electron capture (sometimes called inverse beta decay) is a Decay mode for Isotopes that will occur when there are too many Protons in the 003 163Dy
164Ho syn 29 min ε 0. A synthetic radioisotope is a Radionuclide that is not found in nature no natural process or mechanism exists which produces it or it is so unstable that it decays away in Electron capture (sometimes called inverse beta decay) is a Decay mode for Isotopes that will occur when there are too many Protons in the 987 164Dy
165Ho 100% 165Ho is stable with 98 neutrons
166Ho syn 26. Stable isotopes are chemical isotopes that are not Radioactive (to current knowledge This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. A synthetic radioisotope is a Radionuclide that is not found in nature no natural process or mechanism exists which produces it or it is so unstable that it decays away in 763 h β- 1. In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted 855 166Er
167Ho syn 3. Erbium (ˈɝbiəm is a Chemical element with the symbol Er and Atomic number 68 A synthetic radioisotope is a Radionuclide that is not found in nature no natural process or mechanism exists which produces it or it is so unstable that it decays away in 1 h β- 1. In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted 007 167Er
References

Holmium (pronounced /ˈhoʊlmiəm/) is a chemical element with the symbol Ho and atomic number 67. Erbium (ˈɝbiəm is a Chemical element with the symbol Er and Atomic number 68 Recommended values for many properties of the elements together with various references are collected on these data pages A chemical element is a type of Atom that is distinguished by its Atomic number; that is by the number of Protons in its nucleus. See also List of elements by atomic number In Chemistry and Physics, the atomic number (also known as the proton Part of the lanthanide series, holmium is a relatively soft and malleable silvery-white metallic element, which is stable in dry air at room temperature. Terminology The Trivial name " Rare earths " is sometimes used to describe all the lanthanoids together with Scandium and Yttrium The M acro E xpansion T emplate A ttribute L anguage complements TAL, providing macros which allow the reuse of code across A rare earth metal, it is found in the minerals monazite and gadolinite. Rare earth elements and rare earth metals are according to IUPAC, the collection of seventeen Chemical elements in the Periodic table, namely In Geology, the Mineral monazite is a reddish-brown Phosphate -containing rare earth metals and an important source of Thorium Gadolinite is a Mineral of a nearly black color and vitreous luster, and consisting principally of the silicates of Cerium, Lanthanum

Contents

Notable characteristics

A trivalent metallic rare earth element, holmium has the highest magnetic moment (10. In Physics, Astronomy, Chemistry, and Electrical engineering, the term magnetic moment of a system (such as a loop of Electric current 6µB) of any naturally-occurring element and possesses other unusual magnetic properties. When combined with yttrium, it forms highly magnetic compounds. Yttrium (ˈɪtriəm is a Chemical element with symbol Y and Atomic number 39 In Physics, magnetism is one of the Phenomena by which Materials exert attractive or repulsive Forces on other Materials.

Holmium is a relatively soft and malleable element that is fairly corrosion-resistant and stable in dry air at standard temperature and pressure. Corrosion means the breaking down of essential properties in a material due to Chemical reactions with its surroundings In Physical sciences standard conditions for temperature and pressure are Standard sets of conditions for experimental measurements to allow comparisons to be made In moist air and at higher temperatures, however, it quickly oxidizes, forming a yellowish oxide. Temperature is a physical property of a system that underlies the common notions of hot and cold something that is hotter generally has the greater temperature Redox (shorthand for reduction-oxidation reaction describes all Chemical reactions in which atoms have their Oxidation number ( Oxidation state In pure form, holmium possesses a metallic, bright silvery luster. Holmium oxide has some fairly dramatic color changes depending on the lighting conditions. In daylight, it is a tannish yellow color. Under trichromatic light, it is a fiery orange red, almost indistinguishable from the way erbium oxide looks under this same lighting. This has to do with the sharp emission bands of the phosphors, and the absorption bands of both oxides.

Applications

Because of its magnetic properties, holmium has been used to create the strongest artificially-generated magnetic fields when placed within high-strength magnets as a magnetic pole piece (also called a magnetic flux concentrator). In Physics, a magnetic field is a Vector field that permeates space and which can exert a magnetic force on moving Electric charges A magnet (from Greek grc μαγνήτης λίθος " Magnesian stone" is a material or object that produces a Magnetic field. Since it can absorb nuclear fission-bred neutrons, the element is also used in nuclear control rods. Nuclear fission is the splitting of the nucleus of an atom into parts (lighter nuclei) often producing Free neutrons and other smaller nuclei which may A control rod is a rod made of Chemical elements capable of absorbing many Neutrons without fissioning themselves Other commercial applications of the element include;

Few other uses have been identified for this element.

History

Holmium (Holmia, Latin name for Stockholm) was discovered by Marc Delafontaine and Jacques-Louis Soret in 1878 who noticed the aberrant spectrographic absorption bands of the then-unknown element (they called it "Element X"). Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. ('stɔkhɔlm is Sweden 's Capital and its largest City. It is the site of the national Swedish government, the parliament, and the Marc Delafontaine was a Swiss Chemist who in 1878 along with Jacques-Louis Soret, first observed Holmium spectroscopically Jacques-Louis Soret ( June 30, 1827 &ndash May 13, 1890) was a Swiss Chemist who in 1878 along with Marc Delafontaine Year 1878 ( MDCCCLXXVIII) was a Common year starting on Tuesday (link will display the full calendar of the Gregorian calendar (or a Common In Physics, spectrophotometry is the quantitative study of electromagnetic spectra. An absorption band is a range of Wavelengths (or equivalently frequencies) in the Electromagnetic spectrum which are able to excite a particular [1][2] Later in 1878, Per Teodor Cleve independently discovered the element while he was working on erbia earth (erbium oxide). Per Teodor Cleve ( Stockholm February 10, 1840 &ndash Uppsala June 18, 1905) was a Swedish Chemist Erbium(III oxide, a pink solid is a compound of Erbium sometimes used as a colouring for Glasses and a dopant for optical fibres and optical amplifiers Erbium(III oxide, a pink solid is a compound of Erbium sometimes used as a colouring for Glasses and a dopant for optical fibres and optical amplifiers [3][4]

Using the method developed by Carl Gustaf Mosander, Cleve first removed all of the known contaminants from erbia. Carl Gustaf Mosander ( Kalmar 10 September 1797 &ndash Lovö, Stockholm County 15 October, 1858) was a The result of that effort was two new materials, one brown and one green. He named the brown substance holmia (after the Latin name for Cleve's home town, Stockholm) and the green one thulia. Holmia was later found to be the holmium oxide and thulia was thulium oxide. Holmium(III oxide, is a Chemical compound with the formula Ho2O3 Thulium(III oxide is a pale green solid compound with the formula Tm 2 O 3

Holmium (as the oxide) would not be obtained reasonably pure until the 20th century, and would not become commercially available in high purity until the late 1950's. The Lindsay Chemical Division of American Potash and Chemical Corporation was one of the first producers, using the newly-developed ion-exchange technology to purify holmium as isolated from monazite, in which it was present in trace amounts. In 1960, one pound of 99% holmium oxide was priced at US $105, and the 99. 9% grade cost US $125, which were the same prices as were charged for the comparable oxides of gadolinium, dysprosium, and erbium. One of the early applications was in the form of a glass called a "holmium oxide plate" which was used (by 1965) as a calibration standard for UV/visible spectroscopy.

Occurrence

Like all other rare earths, holmium is not naturally found as a free element. It does occur combined with other elements in the minerals gadolinite, monazite, and in other rare-earth minerals. Gadolinite is a Mineral of a nearly black color and vitreous luster, and consisting principally of the silicates of Cerium, Lanthanum In Geology, the Mineral monazite is a reddish-brown Phosphate -containing rare earth metals and an important source of Thorium A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition a highly ordered atomic structure and specific It is commercially extracted via ion-exchange from monazite sand (0. Ion exchange is an exchange of Ions between two Electrolytes or between an electrolyte Solution and a complex. 05% holmium) but is still difficult to separate from other rare earths. The element has been isolated through the reduction of its anhydrous chloride or fluoride with metallic calcium. Redox (shorthand for reduction-oxidation reaction describes all Chemical reactions in which atoms have their Oxidation number ( Oxidation state The chloride Ion is formed when the element Chlorine picks up one Electron to form an Anion (negatively-charged ion Cl&minus Fluoride is the reduced form of Fluorine. Both organic and Inorganic compounds containing the element fluorine are considered fluorides Calcium (ˈkælsiəm is the Chemical element with the symbol Ca and Atomic number 20 Its estimated abundance in the Earth's crust is 1. EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 3 milligrams per kilogram. Holmium obeys the Oddo-Harkins rule: as an odd-numbered element, it is less abundant than its immediate even numbered neighbors, dysprosium and erbium. The Oddo-Harkins rule holds that elements with an even Atomic number (such as Carbon) are more common than elements with an odd atomic number (such as However, it is the most abundant of the odd-numbered heavy lanthanides. The principal current source are some of the ion-adsorption clays of southern China. Some of these have a rare earth composition similar to that found in xenotime or gadolinite. Yttrium makes up about two-thirds of the total by weight; holmium is around 1. 5%. The original ores themselves are very lean, maybe only 0. 1% total lanthanide, but are easily extracted.

Isotopes

Main article: isotopes of holmium

Natural holmium contains one stable isotope, holmium 165. Natural Holmium ( Ho) contains one Stable Isotope, holmium 165 Nature, in the broadest sense is equivalent to the natural world, physical universe, material world or material universe. A stable is a Building in which Livestock, especially Horses are kept Isotopes (Greek isos = "equal" tópos = "site place" are any of the different types of atoms ( Nuclides Some synthetic radioactive isotopes are known, the most stable one is holmium 163, with a half life of 4570 years. All other radioisotopes have half lives not greater than 1. 117 days, and most have half lives under 3 hours.

Precautions

The element, as with other rare earths, appears to have a low degree of acute toxicity. Holmium plays no biological role in humans but may be able to stimulate metabolism. Human beings, humans or man (Origin 1590–1600 L homō man OL hemō the earthly one (see Humus Metabolism is the set of Chemical reactions that occur in living Organisms in order to maintain Life.

See also

References

  1. ^ Jacques-Louis Soret (1878). Jacques-Louis Soret ( June 30, 1827 &ndash May 13, 1890) was a Swiss Chemist who in 1878 along with Marc Delafontaine "Sur les spectres d'absorption ultra-violets des terres de la gadolinite". Comptes rendus de l'Académie des sciences 87: 1062. Comptes rendus de l'Académie des Sciences, or simply Comptes rendus, is a French scientific journal which has been published since 1835  
  2. ^ Jacques-Louis Soret (1879). "Sur le spectre des terres faisant partie du groupe de l'yttria". Comptes rendus de l'Académie des sciences 89: 521. Comptes rendus de l'Académie des Sciences, or simply Comptes rendus, is a French scientific journal which has been published since 1835  
  3. ^ Per Teodor Cleve (1879). Per Teodor Cleve ( Stockholm February 10, 1840 &ndash Uppsala June 18, 1905) was a Swedish Chemist "Sur deux nouveaux éléments dans l'erbine". Comptes rendus de l'Académie des sciences 89: 478. Comptes rendus de l'Académie des Sciences, or simply Comptes rendus, is a French scientific journal which has been published since 1835  
  4. ^ Per Teodor Cleve (1879). "Sur l'erbine". Comptes rendus de l'Académie des sciences 89: 708. Comptes rendus de l'Académie des Sciences, or simply Comptes rendus, is a French scientific journal which has been published since 1835  

External links

Dictionary

holmium

-noun

  1. a metallic chemical element (symbol Ho) with an atomic number of 67.
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