This article needs additional citations for verification .(December 2009) |
Group 10 in the periodic table | |||||||||
---|---|---|---|---|---|---|---|---|---|
| |||||||||
↓ Period | |||||||||
4 | Nickel (Ni) 28 Transition metal | ||||||||
5 | Palladium (Pd) 46 Transition metal | ||||||||
6 | Platinum (Pt) 78 Transition metal | ||||||||
7 | Darmstadtium (Ds) 110unknown chemical properties | ||||||||
Legend
|
Group 10, numbered by current IUPAC style, is the group of chemical elements in the periodic table that consists of nickel (Ni), palladium (Pd), platinum (Pt), and darmstadtium (Ds). All are d-block transition metals. All known isotopes of darmstadtium are radioactive with short half-lives, and are not known to occur in nature; only minute quantities have been synthesized in laboratories.
Z | Element | No. of electrons per shell | Electronic configuration |
---|---|---|---|
28 | nickel | 2, 8, 16, 2 | [Ar] 3d8 4s2 |
46 | palladium | 2, 8, 18, 18 | [Kr] 4d10 |
78 | platinum | 2, 8, 18, 32, 17, 1 | [Xe] 4f14 5d9 6s1 |
110 | darmstadtium | 2, 8, 18, 32, 32, 16, 2 (predicted) | [Rn] 5f14 6d8 7s2 (predicted) [1] |
The ground state electronic configurations of palladium and platinum are exceptions to Madelung's rule. According to Madelung's rule, the electronic configuration of palladium and platinum are expected to be [Kr] 5s2 4d8 and [Xe] 4f14 5d8 6s2 respectively. However, the 5s orbital of palladium is empty, and the 6s orbital of platinum is only partially filled. The relativistic stabilization of the 7s orbital is the explanation to the predicted electron configuration of darmstadtium, which, unusually for this group, conforms to that predicted by the Aufbau principle.[ citation needed ] In general, the ground state electronic configurations of heavier atoms and transition metals are more difficult to predict.
Group 10 elements are observed in oxidation states of +1 to +4. [2] The +2 oxidation state is common for nickel and palladium, while +2 and +4 are common for platinum. Oxidation states of -2 and -1 have also been observed for nickel [3] [4] and platinum, [5] and an oxidation state of +5 has been observed for palladium [6] and platinum. [7] Platinum has also been observed in oxidations states of -3 [8] and +6. [9] Theory suggests that platinum may produce a +10 oxidation state under specific conditions, but this remains to be shown empirically. [10]
Z | Element | Physical form | Molecular weight | Density (g/cm3) | Melting point (°C) | Boiling point (°C) | Heat capacity/Cp(c) (J mol−1 K−1) | Electron affinity (eV) | Ionization energy (eV) |
---|---|---|---|---|---|---|---|---|---|
28 | nickel | white metal; cubic | 58.693 | 8.90 | 1455 | 2913 | 26.1 | 1.156 | 7.6399 |
46 | palladium | silver-white metal; cubic | 106.42 | 12.0 | 1554.8 | 2963 | 26.0 | 0.562 | 8.3369 |
78 | platinum | silver-gray metal; cubic | 195.048 | 21.5 | 1768.2 | 3825 | 25.9 | 2.128 | 8.9588 |
Darmstadtium has not been isolated in pure form, and its properties have not been conclusively observed; only nickel, palladium, and platinum have had their properties experimentally confirmed. Nickel, platinum, and palladium are typically silvery-white transition metals, and can also be readily obtained in powdered form. [12] They are hard, have a high luster, and are highly ductile. Group 10 elements are resistant to tarnish (oxidation) at STP, are refractory, and have high melting and boiling points.
Nickel occurs naturally in ores, and it is the earth's 22nd most abundant element. Two prominent groups of ores from which it can be extracted are laterites and sulfide ores. [13] Indonesia holds the world's largest nickel reserve, and is also its largest producer. [14]
The use of nickel, often mistaken for copper, dates as far back as 3500 BCE. Nickel has been discovered in a dagger dating to 3100 BCE, in Egyptian iron beads, a bronze reamer found in Syria dating to 3500–3100 BCE, as copper-nickel alloys in coins minted in Bactria, in weapons and pots near the Senegal river, and as agricultural tools used by Mexicans in the 1700s. [10] [15] There is evidence to suggest that the use of nickel in antiquity came from meteoric iron, such as in the Sumerian name for iron an-bar ("fire from heaven") or in Hittite texts that describe iron's heavenly origins. Nickel was not formally named as an element until A. F. Cronstedt isolated the impure metal from "kupfernickel" (Old Nick's copper) in 1751. [11] In 1804, J. B. Richter determined the physical properties of nickel using a purer sample, describing the metal as ductile and strong with a high melting point. The strength of nickel-steel alloys were described in 1889 and since then, nickel steels saw extensive use first for military applications and then in the development of corrosion- and heat-resistant alloys during the 20th century.
Palladium was isolated by William Hyde Wollaston in 1803 while he was working on refining platinum metals. [16] Palladium was in a residue left behind after platinum was precipitated out of a solution of hydrochloric acid and nitric acid as (NH4)PtCl6. [12] Wollaston named it after the recently discovered asteroid 2 Pallas and anonymously sold small samples of the metal to a shop, which advertised it as a "new noble metal" called "Palladium, or New Silver". [17] This raised doubts about its purity, source, and the identity of its discoverer, causing controversy. He eventually identified himself and read his paper on the discovery of palladium to the Royal Society in 1805. [18]
Prior to its formal discovery, platinum was used in jewelry by native Ecuadorians of the province of Esmeraldas. [19] The metal was found in small grains mixed with gold in river deposits, which the workers sintered with gold to form small trinkets such as rings. The first published report of platinum was written by Antonio de Ulloa, a Spanish mathematician, astronomer, and naval officer who observed "platina" (little silver) in the gold mines of Ecuador during a French expedition in 1736. [20] Miners found the "platina" difficult to separate from gold, leading to the abandonment of those mines. Charles Wood (ironmaster) brought samples of the metal to England in 1741 and investigated its properties, observing its high melting point and its presence as small white grains in black metallic sand. Interest in the metal grew after Wood's findings were reported to the Royal Society. Henrik Teofilus Scheffer, a Swedish scientist, referred to the precious metal as "white gold" and the "seventh metal" in 1751, reporting its high durability, high density, and that it melted easily when mixed with copper or arsenic. Both Pierre-François Chabaneau (during the 1780s) and William Hyde Wollaston (during the 1800s) developed a powder metallurgy technique to produce malleable platinum, but kept their process a secret. [19] However, their platinum ingots were brittle and tended to crack easily, likely due to impurities. In the 1800s, furnaces capable of sustaining high temperatures were invented, which eventually replaced powder metallurgy and introduced melted platinum to the market.
The group 10 metals share several uses. These include:
Platinum complexes are commonly used in chemotherapy as anticancer drugs due to their antitumor activity. Palladium complexes also show marginal antitumor activity, yet its poor activity is labile compared to platinum complexes. [16]
{{cite book}}
: CS1 maint: location missing publisher (link) CS1 maint: others (link){{cite book}}
: CS1 maint: others (link)Iridium is a chemical element; it has symbol Ir and atomic number 77. A very hard, brittle, silvery-white transition metal of the platinum group, it is considered the second-densest naturally occurring metal with a density of 22.56 g/cm3 (0.815 lb/cu in) as defined by experimental X-ray crystallography. 191Ir and 193Ir are the only two naturally occurring isotopes of iridium, as well as the only stable isotopes; the latter is the more abundant. It is one of the most corrosion-resistant metals, even at temperatures as high as 2,000 °C (3,630 °F).
A metal is a material that, when polished or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. These properties are all associated with having electrons available at the Fermi level, as against nonmetallic materials which do not. Metals are typically ductile and malleable.
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 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.
Osmium is a chemical element; it has symbol Os and atomic number 76. It is a hard, brittle, bluish-white transition metal in the platinum group that is found as a trace element in alloys, mostly in platinum ores. Osmium is the densest naturally occurring element. When experimentally measured using X-ray crystallography, it has a density of 22.59 g/cm3. Manufacturers use its alloys with platinum, iridium, and other platinum-group metals to make fountain pen nib tipping, electrical contacts, and in other applications that require extreme durability and hardness.
Palladium is a chemical element; it has symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1802 by the English chemist William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired by her when she slew Pallas. Palladium, platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to as the platinum group metals (PGMs). They have similar chemical properties, but palladium has the lowest melting point and is the least dense of them.
Platinum is a chemical element; it has symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal. Its name originates from Spanish platina, a diminutive of plata "little silver".
Ruthenium is a chemical element; it has symbol Ru and atomic number 44. It 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 other chemicals. Karl Ernst Claus, a Russian-born scientist of Baltic-German ancestry, discovered the element in 1844 at Kazan State University and named ruthenium in honor of Russia. Ruthenium is usually found as 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 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.
Rhodium is a chemical element; it has symbol Rh and atomic number 45. It is a very rare, silvery-white, hard, corrosion-resistant transition metal. It is a noble metal and a member of the platinum group. It has only one naturally occurring isotope, which is 103Rh. Naturally occurring rhodium is usually found as a free metal or as an alloy with similar metals and rarely as a chemical compound in minerals such as bowieite and rhodplumsite. It is one of the rarest and most valuable precious metals. Rhodium is a group 9 element.
Darmstadtium is a synthetic chemical element; it has symbol Ds and atomic number 110. It is extremely radioactive: the most stable known isotope, darmstadtium-281, has a half-life of approximately 14 seconds. Darmstadtium was first created in 1994 by the GSI Helmholtz Centre for Heavy Ion Research in the city of Darmstadt, Germany, after which it was named.
Group 6, numbered by IUPAC style, is a group of elements in the periodic table. Its members are chromium (Cr), molybdenum (Mo), tungsten (W), and seaborgium (Sg). These are all transition metals and chromium, molybdenum and tungsten are refractory metals.
A period 5 element is one of the chemical elements in the fifth row of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when chemical behaviour begins to repeat, meaning that elements with similar behaviour fall into the same vertical columns. The fifth period contains 18 elements, beginning with rubidium and ending with xenon. As a rule, period 5 elements fill their 5s shells first, then their 4d, and 5p shells, in that order; however, there are exceptions, such as rhodium.
A noble metal is ordinarily regarded as a metallic element that is generally resistant to corrosion and is usually found in nature in its raw form. Gold, platinum, and the other platinum group metals are most often so classified. Silver, copper, and mercury are sometimes included as noble metals, but each of these usually occurs in nature combined with sulfur.
The platinum-group metals (PGMs), also known as the platinoids, platinides, platidises, platinum group, platinum metals, platinum family or platinum-group elements (PGEs), are six noble, precious metallic elements clustered together in the periodic table. These elements are all transition metals in the d-block.
Group 8 is a group (column) of chemical elements in the periodic table. It consists of iron (Fe), ruthenium (Ru), osmium (Os) and hassium (Hs). "Group 8" is the modern standard designation for this group, adopted by the IUPAC in 1990. It should not be confused with "group VIIIA" in the CAS system, which is group 18, the noble gases. In the older group naming systems, this group was combined with groups 9 and 10 and called group "VIIIB" in the Chemical Abstracts Service (CAS) "U.S. system", or "VIII" in the old IUPAC (pre-1990) "European system". The elements in this group are all transition metals that lie in the d-block of the periodic table.
Group 9, by modern IUPAC numbering, is a group (column) of chemical elements in the d-block of the periodic table. Members of Group 9 include cobalt (Co), rhodium (Rh), iridium (Ir) and meitnerium (Mt). These elements are among the rarest of the transition metals.
Group 12, by modern IUPAC numbering, is a group of chemical elements in the periodic table. It includes zinc (Zn), cadmium (Cd), mercury (Hg), and copernicium (Cn). Formerly this group was named IIB by CAS and old IUPAC system.
A native metal is any metal that is found pure in its metallic form in nature. Metals that can be found as native deposits singly or in alloys include antimony, arsenic, bismuth, cadmium, chromium, cobalt, indium, iron, manganese, molybdenum, nickel, niobium, rhenium, tantalum, tellurium, tin, titanium, tungsten, vanadium, and zinc, as well as the gold group and the platinum group. Among the alloys found in native state have been brass, bronze, pewter, German silver, osmiridium, electrum, white gold, silver-mercury amalgam, and gold-mercury amalgam.
Colored gold is the name given to any gold that has been treated using techniques to change its natural color. Pure gold is slightly reddish yellow in color, but colored gold can come in a variety of different colors by alloying it with different elements.
The metallic elements in the periodic table located between the transition metals to their left and the chemically weak nonmetallic metalloids to their right have received many names in the literature, such as post-transition metals, poor metals, other metals, p-block metals and chemically weak metals. The most common name, post-transition metals, is generally used in this article.