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111-470: The six platinum-group metals are ruthenium , rhodium , palladium , osmium , iridium , and platinum . They have similar physical and chemical properties, and tend to occur together in the same mineral deposits. However, they can be further subdivided into the iridium-group platinum-group elements (IPGEs: Os, Ir, Ru) and the palladium-group platinum-group elements (PPGEs: Rh, Pt, Pd) based on their behaviour in geological systems. The three elements above

222-491: A matte for further refining. Hydrometallurgical techniques are also used. Most sulfide deposits have traditionally been processed by concentration through a froth flotation process followed by pyrometallurgical extraction. The nickel matte is further processed with the Sherritt-Gordon process . First, copper is removed by adding hydrogen sulfide , leaving a concentrate of cobalt and nickel. Then, solvent extraction

333-556: A passivation layer of nickel oxide forms on the surface that prevents further corrosion. Even so, pure native nickel is found in Earth's crust only in tiny amounts, usually in ultramafic rocks , and in the interiors of larger nickel–iron meteorites that were not exposed to oxygen when outside Earth's atmosphere. Meteoric nickel is found in combination with iron , a reflection of the origin of those elements as major end products of supernova nucleosynthesis . An iron–nickel mixture

444-487: A by-product from processing of nickel , copper , and platinum metal ore. During electrorefining of copper and nickel, noble metals such as silver, gold, and the platinum group metals precipitate as anode mud , the feedstock for the extraction. The metals are converted to ionized solutes by any of several methods, depending on the composition of the feedstock. One representative method is fusion with sodium peroxide followed by dissolution in aqua regia , and solution in

555-399: A compound, nickel has a number of niche chemical manufacturing uses, such as a catalyst for hydrogenation , cathodes for rechargeable batteries, pigments and metal surface treatments. Nickel is an essential nutrient for some microorganisms and plants that have enzymes with nickel as an active site . Nickel is a silvery-white metal with a slight golden tinge that takes a high polish. It

666-520: A long-standing controversy between Berzelius and Osann about the composition of the residues. As Osann was not able to repeat his isolation of ruthenium, he eventually relinquished his claims. The name "ruthenium" was chosen by Osann because the analysed samples stemmed from the Ural Mountains in Russia. In 1844, Karl Ernst Claus , a Russian scientist of Baltic German descent, showed that

777-503: A major use of ruthenium. The ruthenium plate is applied to the electrical contact and electrode base metal by electroplating or sputtering . Ruthenium dioxide with lead and bismuth ruthenates are used in thick-film chip resistors. These two electronic applications account for 50% of the ruthenium consumption. Ruthenium is seldom alloyed with metals outside the platinum group, where small quantities improve some properties. The added corrosion resistance in titanium alloys led to

888-419: A minor component of platinum ores; the annual production has risen from about 19 tonnes in 2009 to some 35.5 tonnes in 2017. Most ruthenium produced is used in wear-resistant electrical contacts and thick-film resistors. A minor application for ruthenium is in platinum alloys and as a chemistry catalyst . A new application of ruthenium is as the capping layer for extreme ultraviolet photomasks . Ruthenium

999-430: A mixture of chlorine with hydrochloric acid . Osmium , ruthenium, rhodium , and iridium are insoluble in aqua regia and readily precipitate, leaving the other metals in solution. Rhodium is separated from the residue by treatment with molten sodium bisulfate. The insoluble residue, containing Ru, Os, and Ir is treated with sodium oxide, in which Ir is insoluble, producing dissolved Ru and Os salts. After oxidation to

1110-410: A native metal, but it can also occur in various different minerals and alloys. That said, Sperrylite (platinum arsenide , PtAs 2 ) ore is by far the most significant source of this metal. A naturally occurring platinum-iridium alloy, platiniridium, is found in the mineral cooperite (platinum sulfide , PtS). Platinum in a native state, often accompanied by small amounts of other platinum metals,

1221-713: A public controversy regarding the problems of people with nickel allergy . An estimated 3.6 million tonnes (t) of nickel per year are mined worldwide; Indonesia (1,800,000 t), the Philippines (400,000 t), Russia (200,000 t), New Caledonia ( France ) (230,000 t), Canada (180,000 t) and Australia (160,000 t) are the largest producers as of 2023. The largest nickel deposits in non-Russian Europe are in Finland and Greece . Identified land-based sources averaging at least 1% nickel contain at least 130 million tonnes of nickel. About 60%

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1332-471: A trend that continues to this day – naming an element after a country. Approximately 30.9 tonnes of ruthenium were consumed in 2016, 13.8 of them in electrical applications, 7.7 in catalysis, and 4.6 in electrochemistry. Because it hardens platinum and palladium alloys, ruthenium is used in electrical contacts , where a thin film is sufficient to achieve the desired durability. With its similar properties to and lower cost than rhodium, electric contacts are

1443-504: Is Ni with 28 protons and 50 neutrons. Both are therefore unusually stable for nuclei with so large a proton–neutron imbalance . Nickel-63 is a contaminant found in the support structure of nuclear reactors. It is produced through neutron capture by nickel-62. Small amounts have also been found near nuclear weapon test sites in the South Pacific. Nickel ores are classified as oxides or sulfides. Oxides include laterite , where

1554-465: Is inert (is not chemically reactive ). Some compounds such as ruthenium oxide (RuO 4 ) are highly toxic and volatile. Nickel Nickel is a chemical element ; it has symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal . Pure nickel is chemically reactive, but large pieces are slow to react with air under standard conditions because

1665-411: Is $ 0.045 (90% of the face value). In the 21st century, the high price of nickel has led to some replacement of the metal in coins around the world. Coins still made with nickel alloys include one- and two- euro coins , 5¢, 10¢, 25¢, 50¢, and $ 1 U.S. coins , and 20p, 50p, £1, and £2 UK coins . From 2012 on the nickel-alloy used for 5p and 10p UK coins was replaced with nickel-plated steel. This ignited

1776-687: Is a biological stain used to stain polyanionic molecules such as pectin and nucleic acids for light microscopy and electron microscopy . The beta-decaying isotope 106 of ruthenium is used in radiotherapy of eye tumors, mainly malignant melanomas of the uvea . Ruthenium-centered complexes are being researched for possible anticancer properties. Compared with platinum complexes, those of ruthenium show greater resistance to hydrolysis and more selective action on tumors. Ruthenium tetroxide exposes latent fingerprints by reacting on contact with fatty oils or fats with sebaceous contaminants and producing brown/black ruthenium dioxide pigment. Electronics

1887-417: Is a 3d 4s energy level, specifically the 3d ( F) 4s F, J  = 4 level. However, each of these two configurations splits into several energy levels due to fine structure , and the two sets of energy levels overlap. The average energy of states with [Ar] 3d 4s is actually lower than the average energy of states with [Ar] 3d 4s . Therefore, the research literature on atomic calculations quotes

1998-725: Is a new nickel mine in Michigan's Upper Peninsula . Construction was completed in 2013, and operations began in the third quarter of 2014. In the first full year of operation, the Eagle Mine produced 18,000 t. Nickel is obtained through extractive metallurgy : it is extracted from ore by conventional roasting and reduction processes that yield metal of greater than 75% purity. In many stainless steel applications, 75% pure nickel can be used without further purification, depending on impurities. Traditionally, most sulfide ores are processed using pyrometallurgical techniques to produce

2109-453: Is a rare transition metal belonging to the platinum group of the periodic table . Like the other metals of the platinum group, ruthenium is unreactive to most chemicals. Karl Ernst Claus , a Russian scientist of Baltic-German ancestry, discovered the element in 1844 at Kazan State University and named it in honor of Russia , using the Latin name Ruthenia . Ruthenium is usually found as

2220-431: Is a very rare mineral (Ir replaces part of Ru in its structure). Ruthenium has a relatively high fission product yield in nuclear fission; and given that its most long-lived radioisotope has a half life of "only" around a year, there are often proposals to recover ruthenium in a new kind of nuclear reprocessing from spent fuel . An unusual ruthenium deposit can also be found at the natural nuclear fission reactor that

2331-501: Is a volatile, highly toxic liquid at room temperature. On heating, the complex decomposes back to nickel and carbon monoxide: This behavior is exploited in the Mond process for purifying nickel, as described above. The related nickel(0) complex bis(cyclooctadiene)nickel(0) is a useful catalyst in organonickel chemistry because the cyclooctadiene (or cod ) ligands are easily displaced. Nickel(I) complexes are uncommon, but one example

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2442-469: Is being exposed to halogenated Pt salts, which can cause allergic reactions in high rates of asthma and dermatitis. This is a hazard that can sometimes be seen in the production of industrial catalysts, causing workers to have reactions. Workers removed immediately from further contact with Pt salts showed no evidence of long-term effects, however continued exposure could lead to health effects. Platinum use in drugs also may need to be reevaluated, as some of

2553-444: Is black. Of the dihalides, difluoride is not known, dichloride is brown, dibromide is black, and diiodide is blue. The only known oxyhalide is the pale green ruthenium(VI) oxyfluoride, RuOF 4 . Ruthenium forms a variety of coordination complexes. Examples are the many pentaammine derivatives [Ru(NH 3 ) 5 L] that often exist for both Ru(II) and Ru(III). Derivatives of bipyridine and terpyridine are numerous, best known being

2664-534: Is complex, because it occurs in ores mixed with other metals such as palladium, silver , platinum, and gold . It is found in platinum ores and obtained free as a white inert metal which is very difficult to fuse. Principal sources of this element are located in South Africa, Zimbabwe, in the river sands of the Ural Mountains , North and South America, and also in the copper-nickel sulfide mining area of

2775-409: Is considerable concern for how the accumulation of Pt metal emissions will impact the environment as well as human health. This is a threat that will need more research to determine the safe levels of risk, as well as ways to mitigate potential hazards from platinum group metals. Ruthenium αa 5.77 αc 8.80 Ruthenium is a chemical element ; it has symbol Ru and atomic number 44. It

2886-494: Is contained in spent nuclear fuel , both as a direct fission product and as a product of neutron absorption by long-lived fission product Tc . After allowing the unstable isotopes of ruthenium to decay, chemical extraction could yield ruthenium for use in all applications of ruthenium. Ruthenium can also be produced by deliberate nuclear transmutation from Tc . Given its relatively long half life, high fission product yield and high chemical mobility in

2997-498: Is contaminated by these hazardous Pt metals emitted from VECs. This can potentiality harm other species, including humans if we eat these hazardous animals, such as fish. Platinum metals extracted during the mining and smelting process can also cause significant environmental impacts. In Zimbabwe, a study showed that platinum group mining caused significant environmental risks, such as pollution in water sources, acidic water drainage, and environmental degradation . Another hazard of Pt

3108-703: Is currently being set in place by the International Seabed Authority to ensure that these nodules are collected in an environmentally conscientious manner while adhering to the United Nations Sustainable Development Goals . The one place in the United States where nickel has been profitably mined is Riddle, Oregon , with several square miles of nickel-bearing garnierite surface deposits. The mine closed in 1987. The Eagle mine project

3219-536: Is found in alluvial and placer deposits in Colombia , Ontario , the Ural Mountains , and in certain western American states. Platinum is also produced commercially as a by-product of nickel ore processing. The huge quantities of nickel ore processed makes up for the fact that platinum makes up only two parts per million of the ore. South Africa , with vast platinum ore deposits in the Merensky Reef of

3330-547: Is found in about 100  parts per trillion in the Earth's crust, making it the 78th most abundant element . It is generally found in ores with the other platinum group metals in the Ural Mountains and in North and South America. Small but commercially important quantities are also found in pentlandite extracted from Sudbury , Ontario , Canada, and in pyroxenite deposits in South Africa . The native form of ruthenium

3441-518: Is generally found in ores with the other platinum group metals in the Ural Mountains and in North and South America . Small but commercially important quantities are also found in pentlandite extracted from Sudbury, Ontario , and in pyroxenite deposits in South Africa . Ruthenium, a polyvalent hard white metal, is a member of the platinum group and is in group 8 of the periodic table: Whereas all other group 8 elements have two electrons in

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3552-470: Is greater than both Fe and Fe , more abundant nuclides often incorrectly cited as having the highest binding energy. Though this would seem to predict nickel as the most abundant heavy element in the universe, the high rate of photodisintegration of nickel in stellar interiors causes iron to be by far the most abundant. Nickel-60 is the daughter product of the extinct radionuclide Fe (half-life 2.6 million years). Due to

3663-575: Is in laterites and 40% is in sulfide deposits. Also, extensive nickel sources are found in the depths of the Pacific Ocean , especially in an area called the Clarion Clipperton Zone in the form of polymetallic nodules peppering the seafloor at 3.5–6 km below sea level . These nodules are composed of numerous rare-earth metals and are estimated to be 1.7% nickel. With advances in science and engineering , regulation

3774-496: Is known to be superconductive at temperatures below 10.6 K . Ruthenium is the only 4d transition metal that can assume the group oxidation state +8, and even then it is less stable there than the heavier congener osmium: this is the first group from the left of the table where the second and third-row transition metals display notable differences in chemical behavior. Like iron but unlike osmium, ruthenium can form aqueous cations in its lower oxidation states of +2 and +3. Ruthenium

3885-499: Is mostly used as an intermediate in the purification of ruthenium from ores and radiowastes. Dipotassium ruthenate (K 2 RuO 4 , +6) and potassium perruthenate (KRuO 4 , +7) are also known. Unlike osmium tetroxide, ruthenium tetroxide is less stable, is strong enough as an oxidising agent to oxidise dilute hydrochloric acid and organic solvents like ethanol at room temperature, and is easily reduced to ruthenate ( RuO 4 ) in aqueous alkaline solutions; it decomposes to form

3996-481: Is not as far off the trend in the 4d series as manganese in the 3d transition series.) Unlike the lighter congener iron, ruthenium is paramagnetic at room temperature, as iron also is above its Curie point . The reduction potentials in acidic aqueous solution for some common ruthenium species are shown below: Naturally occurring ruthenium is composed of seven stable isotopes . Additionally, 34 radioactive isotopes have been discovered. Of these radioisotopes ,

4107-500: Is not attacked by acids (even aqua regia ) but is attacked by sodium hypochlorite at room temperature, and halogens at high temperatures. Ruthenium is most readily attacked by oxidizing agents. Small amounts of ruthenium can increase the hardness of platinum and palladium . The corrosion resistance of titanium is increased markedly by the addition of a small amount of ruthenium. The metal can be plated by electroplating and by thermal decomposition. A ruthenium– molybdenum alloy

4218-455: Is now Syria have been found to contain as much as 2% nickel. Some ancient Chinese manuscripts suggest that "white copper" ( cupronickel , known as baitong ) was used there in 1700–1400 BCE. This Paktong white copper was exported to Britain as early as the 17th century, but the nickel content of this alloy was not discovered until 1822. Coins of nickel-copper alloy were minted by Bactrian kings Agathocles , Euthydemus II , and Pantaleon in

4329-434: Is now known as the mineral nickeline (formerly niccolite ), a nickel arsenide . In 1751, Baron Axel Fredrik Cronstedt tried to extract copper from kupfernickel at a cobalt mine in the village of Los, Sweden , and instead produced a white metal that he named nickel after the spirit that had given its name to the mineral. In modern German, Kupfernickel or Kupfer-Nickel designates the alloy cupronickel . Originally,

4440-412: Is one of only four elements that are ferromagnetic at or near room temperature; the others are iron, cobalt and gadolinium . Its Curie temperature is 355 °C (671 °F), meaning that bulk nickel is non-magnetic above this temperature. The unit cell of nickel is a face-centered cube ; it has lattice parameter of 0.352 nm, giving an atomic radius of 0.124 nm. This crystal structure

4551-469: Is produced by the silicon burning process and later set free in large amounts in type Ia supernovae . The shape of the light curve of these supernovae at intermediate to late-times corresponds to the decay via electron capture of Ni to cobalt -56 and ultimately to iron-56. Nickel-59 is a long-lived cosmogenic radionuclide ; half-life 76,000 years. Ni has found many applications in isotope geology . Ni has been used to date

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4662-411: Is recovered commercially as a by-product from nickel mining and processing. Ruthenium is generally found in ores with the other platinum group metals in the Ural Mountains and in North and South America . Small but commercially important quantities are also found in pentlandite extracted from Sudbury, Ontario , and in pyroxenite deposits in South Africa . The industrial extraction of rhodium

4773-656: Is reduced by cold dilute potassium hydroxide to form black potassium perruthenate, KRuO 4 , with ruthenium in the +7 oxidation state. Potassium perruthenate can also be produced by oxidising potassium ruthenate, K 2 RuO 4 , with chlorine gas. The perruthenate ion is unstable and is reduced by water to form the orange ruthenate. Potassium ruthenate may be synthesized by reacting ruthenium metal with molten potassium hydroxide and potassium nitrate . Some mixed oxides are also known, such as M Ru O 3 , Na 3 Ru O 4 , Na 2 Ru 2 O 7 , and M 2 Ln Ru O 6 . The highest known ruthenium halide

4884-572: Is stable to pressures of at least 70 GPa. Nickel is hard, malleable and ductile , and has a relatively high electrical and thermal conductivity for transition metals. The high compressive strength of 34 GPa, predicted for ideal crystals, is never obtained in the real bulk material due to formation and movement of dislocations . However, it has been reached in Ni nanoparticles . Nickel has two atomic electron configurations , [Ar] 3d 4s and [Ar] 3d 4s , which are very close in energy; [Ar] denotes

4995-427: Is the hexafluoride , a dark brown solid that melts at 54 °C. It hydrolyzes violently upon contact with water and easily disproportionates to form a mixture of lower ruthenium fluorides, releasing fluorine gas. Ruthenium pentafluoride is a tetrameric dark green solid that is also readily hydrolyzed, melting at 86.5 °C. The yellow ruthenium tetrafluoride is probably also polymeric and can be formed by reducing

5106-416: Is the first in a downward trend in the melting and boiling points and atomization enthalpy in the 4d transition metals after the maximum seen at molybdenum , because the 4d subshell is more than half full and the electrons are contributing less to metallic bonding. ( Technetium , the previous element, has an exceptionally low value that is off the trend due to its half-filled [Kr]4d 5s configuration, though it

5217-457: Is the largest use of ruthenium. Ru metal is particularly nonvolatile, which is advantageous in microelectronic devices. Ru and its main oxide RuO 2 have comparable electrical resistivities. Copper can be directly electroplated onto ruthenium, particular applications include barrier layers , transistor gates, and interconnects. Ru films can be deposited by chemical vapor deposition using volatile complexes such as ruthenium tetroxide and

5328-446: Is the tetrahedral complex NiBr(PPh 3 ) 3 . Many nickel(I) complexes have Ni–Ni bonding, such as the dark red diamagnetic K 4 [Ni 2 (CN) 6 ] prepared by reduction of K 2 [Ni 2 (CN) 6 ] with sodium amalgam . This compound is oxidized in water, liberating H 2 . It is thought that the nickel(I) oxidation state is important to nickel-containing enzymes, such as [NiFe]-hydrogenase , which catalyzes

5439-631: Is thought to compose Earth's outer and inner cores . Use of nickel (as natural meteoric nickel–iron alloy) has been traced as far back as 3500 BCE. Nickel was first isolated and classified as an element in 1751 by Axel Fredrik Cronstedt , who initially mistook the ore for a copper mineral , in the cobalt mines of Los, Hälsingland, Sweden . The element's name comes from a mischievous sprite of German miner mythology, Nickel (similar to Old Nick ). Nickel minerals can be green, like copper ores, and were known as kupfernickel – Nickel's copper – because they produced no copper. Although most nickel in

5550-479: Is used as the cathode in many rechargeable batteries , including nickel–cadmium , nickel–iron , nickel–hydrogen , and nickel–metal hydride , and used by certain manufacturers in Li-ion batteries . Ni(IV) remains a rare oxidation state and very few compounds are known. Ni(IV) occurs in the mixed oxide BaNiO 3 . Unintentional use of nickel can be traced back as far as 3500 BCE. Bronzes from what

5661-455: Is used chiefly in alloys and corrosion-resistant plating. About 68% of world production is used in stainless steel . A further 10% is used for nickel-based and copper-based alloys, 9% for plating, 7% for alloy steels, 3% in foundries, and 4% in other applications such as in rechargeable batteries, including those in electric vehicles (EVs). Nickel is widely used in coins , though nickel-plated objects sometimes provoke nickel allergy . As

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5772-412: Is used to separate the cobalt and nickel, with the final nickel content greater than 86%. A second common refining process is leaching the metal matte into a nickel salt solution, followed by electrowinning the nickel from solution by plating it onto a cathode as electrolytic nickel. The purest metal is obtained from nickel oxide by the Mond process , which gives a purity of over 99.99%. The process

5883-661: Is used, the chloride complexes are produced. Depending on the details of the process, which are often trade secrets, the individual PGMs are obtained as the following compounds: the poorly soluble (NH 4 ) 2 IrCl 6 and (NH 4 ) 2 PtCl 6 , PdCl 2 (NH 3 ) 2 , the volatile OsO 4 and RuO 4 , and [RhCl(NH 3 ) 5 ]Cl 2 . Significant quantities of the three light platinum group metals—ruthenium, rhodium and palladium—are formed as fission products in nuclear reactors. With escalating prices and increasing global demand, reactor-produced noble metals are emerging as an alternative source. Various reports are available on

5994-492: The Bushveld Igneous Complex because of this. Further research is needed to determine the environmental impacts. Classical purification methods exploit differences in chemical reactivity and solubility of several compounds of the metals under extraction. These approaches have yielded to new technologies that utilize solvent extraction . Separation begins with dissolution of the sample. If aqua regia

6105-579: The Bushveld complex , is the world's largest producer of platinum, followed by Russia . Platinum and palladium are also mined commercially from the Stillwater igneous complex in Montana, USA. Leaders of primary platinum production are South Africa and Russia, followed by Canada, Zimbabwe and USA. Osmiridium is a naturally occurring alloy of iridium and osmium found in platinum-bearing river sands in

6216-587: The Parker 51 fountain pen was fitted with the "RU" nib, a 14K gold nib tipped with 96.2% ruthenium and 3.8% iridium . Ruthenium is a component of mixed-metal oxide (MMO) anodes used for cathodic protection of underground and submerged structures, and for electrolytic cells for such processes as generating chlorine from salt water. The fluorescence of some ruthenium complexes is quenched by oxygen, finding use in optode sensors for oxygen. Ruthenium red , [(NH 3 ) 5 Ru-O-Ru(NH 3 ) 4 -O-Ru(NH 3 ) 5 ] ,

6327-550: The Sudbury Basin region. Although the quantity at Sudbury is very small, the large amount of nickel ore processed makes rhodium recovery cost effective. However, the annual world production in 2003 of this element is only 7 or 8 tons and there are very few rhodium minerals. Palladium is preferentially hosted in sulphide minerals, primarily in pyrrhotite . Palladium is found as a free metal and alloyed with platinum and gold with platinum group metals in placer deposits of

6438-627: The Ural Mountains and in North and South America . Trace amounts of osmium also exist in nickel-bearing ores found in the Sudbury , Ontario , region along with other platinum group metals. Even though the quantity of platinum metals found in these ores is small, the large volume of nickel ores processed makes commercial recovery possible. Metallic iridium is found with platinum and other platinum group metals in alluvial deposits. Naturally occurring iridium alloys include osmiridium and iridosmine , both of which are mixtures of iridium and osmium. It

6549-416: The Ural Mountains of Eurasia , Australia , Ethiopia , South and North America . However it is commercially produced from nickel- copper deposits found in South Africa and Ontario, Canada . The huge volume of nickel-copper ore processed makes this extraction profitable in spite of its low concentration in these ores. The production of individual platinum group metals normally starts from residues of

6660-467: The arsenide niccolite . Identified land-based resources throughout the world averaging 1% nickel or greater comprise at least 130 million tons of nickel (about the double of known reserves). About 60% is in laterites and 40% in sulfide deposits. On geophysical evidence, most of the nickel on Earth is believed to be in Earth's outer and inner cores . Kamacite and taenite are naturally occurring alloys of iron and nickel. For kamacite,

6771-762: The luminescent tris(bipyridine)ruthenium(II) chloride . Ruthenium forms a wide range compounds with carbon–ruthenium bonds. Grubbs' catalyst is used for alkene metathesis. Ruthenocene is analogous to ferrocene structurally, but exhibits distinctive redox properties. The colorless liquid ruthenium pentacarbonyl converts in the absence of CO pressure to the dark red solid triruthenium dodecacarbonyl . Ruthenium trichloride reacts with carbon monoxide to give many derivatives including RuHCl(CO)(PPh 3 ) 3 and Ru(CO) 2 (PPh 3 ) 3 ( Roper's complex ). Heating solutions of ruthenium trichloride in alcohols with triphenylphosphine gives tris(triphenylphosphine)ruthenium dichloride (RuCl 2 (PPh 3 ) 3 ), which converts to

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6882-484: The metal aquo complex [Ni(H 2 O) 6 ] . The four halides form nickel compounds, which are solids with molecules with octahedral Ni centres. Nickel(II) chloride is most common, and its behavior is illustrative of the other halides. Nickel(II) chloride is made by dissolving nickel or its oxide in hydrochloric acid . It is usually found as the green hexahydrate, whose formula is usually written NiCl 2 ·6H 2 O . When dissolved in water, this salt forms

6993-479: The metal aquo complex [Ni(H 2 O) 6 ] . Dehydration of NiCl 2 ·6H 2 O gives yellow anhydrous NiCl 2 . Some tetracoordinate nickel(II) complexes, e.g. bis(triphenylphosphine)nickel chloride , exist both in tetrahedral and square planar geometries. The tetrahedral complexes are paramagnetic ; the square planar complexes are diamagnetic . In having properties of magnetic equilibrium and formation of octahedral complexes, they contrast with

7104-490: The organoruthenium compound ( cyclohexadiene )Ru(CO) 3 . Many ruthenium-containing compounds exhibit useful catalytic properties. Solutions containing ruthenium trichloride are highly active for olefin metathesis . Such catalysts are used commercially for the production of polynorbornene for example. Well defined ruthenium carbene and alkylidene complexes show similar reactivity but are only used on small-scale. The Grubbs' catalysts for example have been employed in

7215-543: The 2nd century BCE, possibly out of the Chinese cupronickel. In medieval Germany, a metallic yellow mineral was found in the Ore Mountains that resembled copper ore. But when miners were unable to get any copper from it, they blamed a mischievous sprite of German mythology, Nickel (similar to Old Nick ), for besetting the copper. They called this ore Kupfernickel from German Kupfer 'copper'. This ore

7326-504: The United States, the term "nickel" or "nick" originally applied to the copper-nickel Flying Eagle cent , which replaced copper with 12% nickel 1857–58, then the Indian Head cent of the same alloy from 1859 to 1864. Still later, in 1865, the term designated the three-cent nickel , with nickel increased to 25%. In 1866, the five-cent shield nickel (25% nickel, 75% copper) appropriated the designation, which has been used ever since for

7437-468: The accumulation of platinum group metals in the environment may actually pose more of a risk than previously thought. Future research is needed to fully grasp the threat of platinum metals, especially since as more internal combustion cars are driven, the more platinum metal emissions there are. The bioaccumulation of Pt metals in animals can pose a significant health risk to both humans and biodiversity. Species will tend to get more toxic if their food source

7548-501: The alloy is usually in the proportion of 90:10 to 95:5, though impurities (such as cobalt or carbon ) may be present. Taenite is 20% to 65% nickel. Kamacite and taenite are also found in nickel iron meteorites . Nickel is commonly found in iron meteorites as the alloys kamacite and taenite . Nickel in meteorites was first detected in 1799 by Joseph-Louis Proust , a French chemist who then worked in Spain. Proust analyzed samples of

7659-589: The asteroid Vesta discovered shortly before) from South American platinum ores in 1807. He published an announcement of his discovery in 1808. His work was never confirmed, however, and he later withdrew his claim of discovery. Jöns Berzelius and Gottfried Osann nearly discovered ruthenium in 1827. They examined residues that were left after dissolving crude platinum from the Ural Mountains in aqua regia . Berzelius did not find any unusual metals, but Osann thought he found three new metals, which he called pluranium, ruthenium, and polinium. This discrepancy led to

7770-469: The complete argon core structure. There is some disagreement on which configuration has the lower energy. Chemistry textbooks quote nickel's electron configuration as [Ar] 4s 3d , also written [Ar] 3d 4s . This configuration agrees with the Madelung energy ordering rule , which predicts that 4s is filled before 3d. It is supported by the experimental fact that the lowest energy state of the nickel atom

7881-502: The compounds prepared by Gottfried Osann contained small amounts of ruthenium, which Claus had discovered the same year. Claus isolated ruthenium from the platinum residues of rouble production while he was working in Kazan University , Kazan , the same way its heavier congener osmium had been discovered four decades earlier. Claus showed that ruthenium oxide contained a new metal and obtained 6 grams of ruthenium from

7992-465: The development of a special alloy with 0.1% ruthenium. Ruthenium is also used in some advanced high-temperature single-crystal superalloys , with applications that include the turbines in jet engines . Several nickel based superalloy compositions are described, such as EPM-102 (with 3% Ru), TMS-162 (with 6% Ru), TMS-138, and TMS-174, the latter two containing 6% rhenium . Fountain pen nibs are frequently tipped with ruthenium alloy. From 1944 onward,

8103-471: The dioxide above 100 °C. Unlike iron but like osmium, ruthenium does not form oxides in its lower +2 and +3 oxidation states. Ruthenium forms di chalcogenides , which are diamagnetic semiconductors crystallizing in the pyrite structure. Ruthenium sulfide (RuS 2 ) occurs naturally as the mineral laurite . Like iron, ruthenium does not readily form oxoanions and prefers to achieve high coordination numbers with hydroxide ions instead. Ruthenium tetroxide

8214-484: The divalent complexes of the heavier group 10 metals, palladium(II) and platinum(II), which form only square-planar geometry. Nickelocene has an electron count of 20. Many chemical reactions of nickelocene tend to yield 18-electron products. Many Ni(III) compounds are known. Ni(III) forms simple salts with fluoride or oxide ions. Ni(III) can be stabilized by σ-donor ligands such as thiols and organophosphines . Ni(III) occurs in nickel oxide hydroxide , which

8325-647: The earth's crust exists as oxides, economically more important nickel ores are sulfides, especially pentlandite . Major production sites include the Sudbury region , Canada (which is thought to be of meteoric origin), New Caledonia in the Pacific , Western Australia , and Norilsk , Russia. Nickel is one of four elements (the others are iron , cobalt , and gadolinium ) that are ferromagnetic at about room temperature. Alnico permanent magnets based partly on nickel are of intermediate strength between iron-based permanent magnets and rare-earth magnets . The metal

8436-410: The environment, Tc is among the most often proposed non- actinides for commercial scale nuclear transmutation. Tc has a relatively large neutron cross section , and because technetium has no stable isotopes, there would not be a problem of neutron activation of stable isotopes. Significant amounts of Tc are produced in nuclear fission. They are also produced as a byproduct of

8547-416: The exhaust system of vehicles to reduce harmful emissions, such as carbon monoxide (CO), by converting them into less harmful emissions. Generally, ultramafic and mafic igneous rocks have relatively high, and granites low, PGE trace content. Geochemically anomalous traces occur predominantly in chromian spinels and sulfides. Mafic and ultramafic igneous rocks host practically all primary PGM ore of

8658-422: The future. For example, metallic Pt are considered to not be chemically reactive and non-allergenic, so when Pt is emitted from VECs it is in metallic and oxide forms it is considered relatively safe. However, Pt can solubilise in road dust, enter water sources, the ground, and increase dose rates in animals through bioaccumulation . These impacts from platinum groups were previously not considered, however over time

8769-479: The ground state configuration as [Ar] 3d 4s . The isotopes of nickel range in atomic weight from 48  u ( Ni ) to 82 u ( Ni ). Natural nickel is composed of five stable isotopes , Ni , Ni , Ni , Ni and Ni , of which Ni is the most abundant (68.077% natural abundance ). Nickel-62 has the highest binding energy per nucleon of any nuclide : 8.7946 MeV/nucleon. Its binding energy

8880-455: The hydride complex chlorohydridotris(triphenylphosphine)ruthenium(II) (RuHCl(PPh 3 ) 3 ). Though naturally occurring platinum alloys containing all six platinum-group metals were used for a long time by pre-Columbian Americans and known as a material to European chemists from the mid-16th century, not until the mid-18th century was platinum identified as a pure element. That natural platinum contained palladium, rhodium, osmium and iridium

8991-512: The large deposits in the Sudbury Basin in Canada in 1883, in Norilsk -Talnakh in Russia in 1920, and in the Merensky Reef in South Africa in 1924 made large-scale nickel production possible. Aside from the aforementioned Bactrian coins, nickel was not a component of coins until the mid-19th century. 99.9% nickel five-cent coins were struck in Canada (the world's largest nickel producer at

9102-784: The long half-life of Fe , its persistence in materials in the Solar System may generate observable variations in the isotopic composition of Ni . Therefore, the abundance of Ni in extraterrestrial material may give insight into the origin of the Solar System and its early history. At least 26 nickel radioisotopes have been characterized; the most stable are Ni with half-life 76,000 years, Ni (100 years), and Ni (6 days). All other radioisotopes have half-lives less than 60 hours and most these have half-lives less than 30 seconds. This element also has one meta state . Radioactive nickel-56

9213-607: The metal was used by pre-Columbian peoples, the first European reference to platinum appears in 1557 in the writings of the Italian humanist Julius Caesar Scaliger (1484–1558) as a description of a mysterious metal found in Central American mines between Darién (Panama) and Mexico ("up until now impossible to melt by any of the Spanish arts"). The name platinum is derived from the Spanish word platina ("little silver"),

9324-416: The metals at a profit. The United States Mint , anticipating this practice, implemented new interim rules on December 14, 2006, subject to public comment for 30 days, which criminalized the melting and export of cents and nickels. Violators can be punished with a fine of up to $ 10,000 and/or a maximum of five years in prison. As of September 19, 2013, the melt value of a US nickel (copper and nickel included)

9435-446: The meteorite from Campo del Cielo (Argentina), which had been obtained in 1783 by Miguel Rubín de Celis, discovering the presence in them of nickel (about 10%) along with iron. The most common oxidation state of nickel is +2, but compounds of Ni , Ni , and Ni are well known, and the exotic oxidation states Ni and Ni have been characterized. Nickel tetracarbonyl (Ni(CO) 4 ), discovered by Ludwig Mond ,

9546-455: The mined platinum group metal (PGM) mixtures varies widely, depending on the geochemical formation. For example, the PGMs mined in South Africa contain on average 11% ruthenium while the PGMs mined in the former USSR contain only 2% (1992). Ruthenium, osmium, and iridium are considered the minor platinum group metals. Ruthenium, like the other platinum group metals, is obtained commercially as

9657-423: The most abundant isotope, Ru, is electron capture while the primary mode after is beta emission . The primary decay product before Ru is technetium and the primary decay product after is rhodium . Ru is a product of fission of a nucleus of uranium or plutonium . High concentrations of detected atmospheric Ru were associated with an alleged undeclared nuclear accident in Russia in 2017. Ruthenium

9768-471: The most common. The most prevalent precursor is ruthenium trichloride , a red solid that is poorly defined chemically but versatile synthetically. Ruthenium can be oxidized to ruthenium(IV) oxide (RuO 2 , oxidation state +4), which can, in turn, be oxidized by sodium metaperiodate to the volatile yellow tetrahedral ruthenium tetroxide , RuO 4 , an aggressive, strong oxidizing agent with structure and properties analogous to osmium tetroxide . RuO 4

9879-452: The most stable are Ru with a half-life of 373.59 days, Ru with a half-life of 39.26 days and Ru with a half-life of 2.9 days. Fifteen other radioisotopes have been characterized with atomic weights ranging from 89.93  Da ( Ru) to 114.928 Da ( Ru). Most of these have half-lives that are less than five minutes; the exceptions are Ru (half-life: 1.643 hours) and Ru (half-life: 4.44 hours). The primary decay mode before

9990-927: The name given to the metal by Spanish settlers in Colombia . They regarded platinum as an unwanted impurity in the silver they were mining. By 1815, rhodium and palladium had been discovered by William Hyde Wollaston , and iridium and osmium by his close friend and collaborator Smithson Tennant . The platinum metals have many useful catalytic properties. They are highly resistant to wear and tarnish, making platinum, in particular, well suited for fine jewellery . Other distinctive properties include resistance to chemical attack, excellent high-temperature characteristics, high mechanical strength, good ductility, and stable electrical properties. Apart from their application in jewellery, platinum metals are also used in anticancer drugs, industries, dentistry, electronics, and vehicle exhaust catalysts (VECs). VECs contain solid platinum (Pt), palladium (Pd), and rhodium (Rh) and are installed in

10101-509: The only source for nickel was the rare Kupfernickel. Beginning in 1824, nickel was obtained as a byproduct of cobalt blue production. The first large-scale smelting of nickel began in Norway in 1848 from nickel-rich pyrrhotite . The introduction of nickel in steel production in 1889 increased the demand for nickel; the nickel deposits of New Caledonia , discovered in 1865, provided most of the world's supply between 1875 and 1915. The discovery of

10212-448: The outermost shell, in ruthenium the outermost shell has only one electron (the final electron is in a lower shell). This anomaly is also observed in the neighboring metals niobium (41), molybdenum (42), and rhodium (45). Ruthenium has four crystal modifications and does not tarnish at ambient conditions; it oxidizes upon heating to 800 °C (1,070 K). Ruthenium dissolves in fused alkalis to give ruthenates ( RuO 4 ). It

10323-400: The part of crude platinum that is insoluble in aqua regia . Choosing the name for the new element, Claus stated: "I named the new body, in honour of my Motherland, ruthenium. I had every right to call it by this name because Mr. Osann relinquished his ruthenium and the word does not yet exist in chemistry." The name itself derives from the Latin word Ruthenia . In doing so, Claus started

10434-432: The pentafluoride with iodine . Among the binary compounds of ruthenium, these high oxidation states are known only in the oxides and fluorides. Ruthenium trichloride is a well-known compound, existing in a black α-form and a dark brown β-form: the trihydrate is red. Of the known trihalides, trifluoride is dark brown and decomposes above 650 °C, tribromide is dark-brown and decomposes above 400 °C, and triiodide

10545-406: The platinum group in the periodic table ( iron , nickel and cobalt ) are all ferromagnetic ; these, together with the lanthanide element gadolinium (at temperatures below 20 °C), are the only known transition metals that display ferromagnetism near room temperature. Naturally occurring platinum and platinum-rich alloys were known by pre-Columbian Americans for many years. However, even though

10656-434: The possibility of recovering fission noble metals from spent nuclear fuel . It was previously thought that platinum group metals had very few negative attributes in comparison to their distinctive properties and their ability to successfully reduce harmful emission from automobile exhausts. However, even with all the positives of platinum metal use, the negative effects of their use need to be considered in how it might impact

10767-483: The preparation of drugs and advanced materials. Some ruthenium complexes are highly active catalysts for transfer hydrogenations (sometimes referred to as "borrowing hydrogen" reactions). Chiral ruthenium complexes, introduced by Ryoji Noyori , are employed for the enantioselective hydrogenation of ketones , aldehydes , and imines . A typical catalyst is (cymene)Ru(S,S-Ts DPEN ): A Nobel Prize in Chemistry

10878-407: The principal mineral mixtures are nickeliferous limonite , (Fe,Ni)O(OH), and garnierite (a mixture of various hydrous nickel and nickel-rich silicates). Nickel sulfides commonly exist as solid solutions with iron in minerals such as pentlandite and pyrrhotite with the formula Fe 9-x Ni x S 8 and Fe 7-x Ni x S 6 , respectively. Other common Ni-containing minerals are millerite and

10989-421: The production of other metals with a mixture of several of those metals. Purification typically starts with the anode residues of gold, copper, or nickel production. This results in a very energy intensive extraction process, which leads to environmental consequences. Carbon dioxide emissions are expected to rise as a result of increased demand for platinum metals and there is likely to be expanded mining activity in

11100-477: The reversible reduction of protons to H 2 . Nickel(II) forms compounds with all common anions, including sulfide , sulfate , carbonate, hydroxide, carboxylates, and halides. Nickel(II) sulfate is produced in large amounts by dissolving nickel metal or oxides in sulfuric acid , forming both a hexa- and heptahydrate useful for electroplating nickel. Common salts of nickel, such as chloride, nitrate, and sulfate, dissolve in water to give green solutions of

11211-510: The side effects to these drugs include nausea, hearing loss, and nephrotoxicity. Handling of these drugs by professionals, such as nurses, have also resulted in some side effects including chromosome aberrations and hair loss. Therefore, the long term effects of platinum drug use and exposure need to be evaluated and considered to determine if they are safe to use in medical care. While exposure of relatively low volumes of platinum group metal emissions may not have any long-term health effects, there

11322-468: The subsequent 5-cent pieces. This alloy proportion is not ferromagnetic . The US nickel coin contains 0.04 ounces (1.1 g) of nickel, which at the April 2007 price was worth 6.5 cents, along with 3.75 grams of copper worth about 3 cents, with a total metal value of more than 9 cents. Since the face value of a nickel is 5 cents, this made it an attractive target for melting by people wanting to sell

11433-399: The terrestrial age of meteorites and to determine abundances of extraterrestrial dust in ice and sediment . Nickel-78, with a half-life of 110 milliseconds, is believed an important isotope in supernova nucleosynthesis of elements heavier than iron. Ni, discovered in 1999, is the most proton-rich heavy element isotope known. With 28 protons and 20 neutrons , Ni is " doubly magic ", as

11544-563: The time) during non-war years from 1922 to 1981; the metal content made these coins magnetic. During the war years 1942–1945, most or all nickel was removed from Canadian and US coins to save it for making armor. Canada used 99.9% nickel from 1968 in its higher-value coins until 2000. Coins of nearly pure nickel were first used in 1881 in Switzerland. Birmingham forged nickel coins in c.  1833 for trading in Malaysia. In

11655-490: The use of Tc in nuclear medicine , because this isomer decays to Tc . Exposing the Tc target to strong enough neutron radiation will eventually yield appreciable quantities of ruthenium, which can be chemically separated while consuming Tc . The oxidation states of ruthenium range from 0 to +8, and −2. The properties of ruthenium and osmium compounds are often similar. The +2, +3, and +4 states are

11766-490: The volatile oxides, RuO 4 is separated from OsO 4 by precipitation of (NH 4 ) 3 RuCl 6 with ammonium chloride or by distillation or extraction with organic solvents of the volatile osmium tetroxide. Hydrogen is used to reduce ammonium ruthenium chloride, yielding a powder. The product is reduced using hydrogen, yielding the metal as a powder or sponge metal that can be treated with powder metallurgy techniques or argon - arc welding . Ruthenium

11877-544: The world. Mafic layered intrusions , including the Bushveld Complex , outweigh by far all other geological settings of platinum deposits. Other economically significant PGE deposits include mafic intrusions related to flood basalts , and ultramafic complexes of the Alaska, Urals type. Typical ores for PGMs contain ca. 10 g PGM/ton ore, thus the identity of the particular mineral is unknown. Platinum can occur as

11988-555: Was active in Oklo , Gabon, some two billion years ago. Indeed, the isotope ratio of ruthenium found there was one of several ways used to confirm that a nuclear fission chain reaction had indeed occurred at that site in the geological past. Uranium is no longer mined at Oklo, and there have never been serious attempts to recover any of the platinum group metals present there. Roughly 30 tonnes of ruthenium are mined each year, and world reserves are estimated at 5,000 tonnes. The composition of

12099-513: Was awarded in 2001 to Ryōji Noyori for contributions to the field of asymmetric hydrogenation . Ruthenium-promoted cobalt catalysts are used in Fischer–Tropsch synthesis . Ruthenium-based compounds are components of dye-sensitized solar cells , which are proposed as low-cost solar cell system. Little is known about the health effects of ruthenium and it is relatively rare for people to encounter ruthenium compounds. Metallic ruthenium

12210-670: Was discovered in the first decade of the 19th century. Platinum in alluvial sands of Russian rivers gave access to raw material for use in plates and medals and for the minting of ruble coins , starting in 1828. Residues from platinum production for coinage were available in the Russian Empire, and therefore most of the research on them was done in Eastern Europe. It is possible that the Polish chemist Jędrzej Śniadecki isolated element 44 (which he called "vestium" after

12321-429: Was patented by Ludwig Mond and has been in industrial use since before the beginning of the 20th century. In this process, nickel is treated with carbon monoxide in the presence of a sulfur catalyst at around 40–80 °C to form nickel carbonyl . In a similar reaction with iron, iron pentacarbonyl can form, though this reaction is slow. If necessary, the nickel may be separated by distillation. Dicobalt octacarbonyl

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