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palladium
pal·la·di·um 1 P0025900 (pə-lā′dē-əm)n. Symbol Pd A soft, ductile, lustrous gray-white, tarnish-resistant, metallic element occurring naturally with platinum, especially in gold, nickel, and copper ores. Because it can absorb large amounts of hydrogen, it is used as a purification filter for hydrogen and a catalyst in hydrogenation. It is alloyed for use in electric contacts, jewelry, nonmagnetic watch parts, and surgical instruments. Atomic number 46; atomic weight 106.4; melting point 1,554.8°C; boiling point 2,963°C; specific gravity 12.02 (20°C); valence 2, 3, 4. See Periodic Table.
[From Pallas (discovered at the same time as the element).]
pal·la·di·um 2 P0025900 (pə-lā′dē-əm)n. pl. pal·la·di·a (-dē-ə) or pal·la·di·ums 1. A safeguard, especially one viewed as a guarantee of the integrity of social institutions: the Bill of Rights, palladium of American civil liberties.2. A sacred object that was believed to have the power to preserve a city or state possessing it.
[Middle English Palladion, a statue of Pallas Athena believed to protect Troy, from Old French palladion, from Latin Palladium, from Greek Palladion, from Pallas, Pallad-, Pallas Athena.]palladium (pəˈleɪdɪəm) n (Elements & Compounds) a ductile malleable silvery-white element of the platinum metal group occurring principally in nickel-bearing ores: used as a hydrogenation catalyst and, alloyed with gold, in jewellery. Symbol: Pd; atomic no: 46; atomic wt: 106.42; valency: 2, 3, or 4; relative density: 1202; melting pt: 1555°C; boiling pt: 2964°C[C19: named after the asteroid Pallas, at the time (1803) a recent discovery]
palladium (pəˈleɪdɪəm) nsomething believed to ensure protection; safeguard[C17: after the Palladium]
Palladium (pəˈleɪdɪəm) n (Classical Myth & Legend) a statue of Pallas Athena, esp the one upon which the safety of Troy dependedpal•la•di•um (pəˈleɪ di əm)
n. a rare silver-white ductile metallic element of the platinum group, used chiefly as a catalyst and in dental and other alloys. Symbol: Pd; at. wt.: 106.4; at. no.: 46; sp. gr.: 12 at 20°C. [1803; after the asteroid Pallas, then newly discovered; see Palladium, -ium2] pal•lad′ic (-ˈlæd ɪk) pal•la′dous (pəˈleɪ dəs, ˈpæl ə dəs) adj. Pal•la•di•um (pəˈleɪ di əm)
n., pl. -di•a (-di ə) 1. a statue of Athena, esp. one on the citadel of Troy on which the safety of the city was supposed to depend. 2. (usu. l.c.) anything believed to provide protection or safety; safeguard. [< Latin Palladium < Greek Palládion, n. use of neuter of Palládios of Pallas, derivative of Pallás, s. Pallad- Pallas] pal·la·di·um (pə-lā′dē-əm) Symbol Pd An easily shaped, grayish-white metallic element that occurs naturally with platinum. Because it can absorb large amounts of hydrogen, it is used as a catalyst in reactions involving hydrogen. Palladium and its alloys are used to make electrical contacts and jewelry. Atomic number 46. See Periodic Table.Thesaurus| Noun | 1. |  palladium - a silver-white metallic element of the platinum group that resembles platinum; occurs in some copper and nickel ores; does not tarnish at ordinary temperatures and is used (alloyed with gold) in jewelryatomic number 46, Pdmetal, metallic element - any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc. |
Translations
palladium
Palladium (pəlā`dēəm), in Greek religion, sacred image kept in the temple of Athena at Troy. It was either an image of Athena or an image made by Athena of her unfortunate playmate Pallas (see PallasPallas
, in classical mythology. 1 Name given to Athena after she killed either a youthful playmate named Pallas or, in some legends, the giant Pallas. 2 Goatish giant killed by Athena when he tried to rape her.
..... Click the link for more information. (1)). According to legend, the image was sent by Zeus to Dardanus, the founder of Troy, and it was believed that the city could not be taken while it possessed the Palladium. Thus during the Trojan War two Greeks, Diomed and Odysseus, stole it. Another legend says that during the sack of Troy, Ajax the Lesser carried it off. The Romans, who later claimed to have the true Palladium in their temple of the vestal virgins, said that Aeneas took it when he fled Troy. But many cities, including Argos, Athens, and Luceria, owned such images, all of which came to be known as Palladia.
palladium [Gr. Pallas, goddess of wisdom], metallic chemical element; symbol Pd; at. no. 46; at. wt. 106.42; m.p. 1,554°C;; b.p. 2,970°C;; sp. gr. 12.02 at 20°C;; valence +2, +3, or +4. Palladium is a lustrous silver-white metal with a face-centered cubic crystalline structure. Directly above platinum, it is one of the platinum metals in Group 10 of the periodic tableperiodic table,
chart of the elements arranged according to the periodic law discovered by Dmitri I. Mendeleev and revised by Henry G. J. Moseley. In the periodic table the elements are arranged in columns and rows according to increasing atomic number (see the table entitled
..... Click the link for more information. . It is strongly resistant to corrosion in air and to the action of acids (except nitric acid) at ordinary temperatures. However, it is attacked by hot acids, and it dissolves in aqua regia. It forms many compounds, including oxides, chlorides, fluorides, sulfides, phosphides, and several complex salts. Palladium has a great ability to absorb hydrogen; when finely divided, one volume of palladium absorbs as many as 900 volumes of the gas. When heated, it allows hydrogen to diffuse rapidly through it; it is thus used to purify hydrogen gas. Palladium is found in nature with platinum minerals and in association with certain nickel ores; the primary palladium-mining countries are South Africa and Russia. Because of its corrosion resistance, one important use of palladium is in alloys used in low voltage electrical contacts. Palladium is used extensively in jewelry-making in certain alloys called "white gold." It may be alloyed with platinum or substituted for it. It is used in watch bearings, springs, and balance wheels, in surgical instruments, and also for mirrors in scientific instruments. For use in dentistry it is alloyed with silver, gold, and copper. In chemistry it is a catalyst in sulfuric acid manufacture and in hydrogenation processes; it used as a catalyst also in motor vehicle catalytic converters, the use that now consumes more than three fourths of the palladium produced. Palladium salts are used in electroplating. Palladium is not as abundant as platinum, but it was long less expensive. Palladium was discovered in 1803 by W. H. WollastonWollaston, William Hyde,
1766–1828, English scientist, M.D. Cambridge, 1793. His wide-ranging scientific achievements include the discovery (1802) of the dark lines (Fraunhofer lines) in the solar spectrum; invention of the reflecting goniometer (an instrument by which the
..... Click the link for more information. . Palladium (Pd), a chemical element in Group VIII of the Mendeleev periodic system. Atomic number, 46; atomic weight, 106.4. A heavy refractory metal. (SeePLATINUM METALS.) palladium[pə′lād·ē·əm] (chemistry) A chemical element, symbol Pd, atomic number 46, atomic weight 106.4. (metallurgy) A white, ductile malleable metal that resembles platinum and follows it in abundance and importance of applications; does not tarnish at normal temperatures. palladiuma “safeguard”; Troy believed safe while statue of Pallas Athene remained. [Gk. Lit.: Iliad; Espy, 40]See: Guardianship
Palladiumcolossal statue whose presence insured Troy’s safety. [Rom. Legend: Brewer Dictionary, 796]See: Protectivenesspalladium a ductile malleable silvery-white element of the platinum metal group occurring principally in nickel-bearing ores: used as a hydrogenation catalyst and, alloyed with gold, in jewellery. Symbol: Pd; atomic no.: 46; atomic wt.: 106.42; valency: 2, 3, or 4; relative density: 1202; melting pt.: 1555°C; boiling pt.: 2964°C palladiumA silvery metal similar to platinum. Palladium was the original name of Microsoft's security platform (see NGSCB).palladium
palladium (Pd) [pah-la´de-um] a chemical element, atomic number 46, atomic weight 106.4. (See Appendix 6.) It is used in alloys for dental and orthodontic appliances.pal·la·di·um (Pd), (pă-lā'dē-ŭm), A metallic element resembling platinum, atomic no. 46, atomic wt. 106.42. [fr. the asteroid, Pallas; G. Pallas, goddess of wisdom] pal·la·di·um (pă-lā'dē-ŭm) A metallic element resembling platinum, atomic no. 46, atomic wt. 106.42. [fr. the asteroid, Pallas; G. Pallas, Athena goddess of wisdom]pal·la·di·um (Pd) (pă-lā'dē-ŭm) A metallic element resembling platinum. Palladium
PalladiumA precious metal that may be used in jewelry, electronics, or other products. It may be traded as a commodity or on the futures and option markets.AcronymsSeeperiodpalladium
Synonyms for palladiumnoun a silver-white metallic element of the platinum group that resembles platinumSynonymsRelated Words |