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Kurnakov Test
The Kurnakov test, also known as Kurnakov's reaction, is a chemical test that distinguishes pairs of Cis isomer, ''cis''- and trans-isomers, ''trans''-isomers of [PtA2X2] (A = NH3, X = halogen or pseudohalide). Upon treatment with thiourea, the ''trans''-dihalides give less soluble white products, whereas the ''cis''-dihalides give more soluble yellow products. The test is still used to assay samples of the drug cisplatin, but it is mainly of pedagogical interest, as it illustrates the trans effect. The test was devised by Soviet Union, Soviet chemist Nikolai Kurnakov. Application The Kurnakov test is sometimes used to detect transplatin in samples of the drug cisplatin. In hot aqueous solution, the ''cis''-compound reacts with aqueous thiourea (tu) to give a deeper yellow solution, from which yellow needles of [Pt(tu)4]Cl2 chloride deposit on cooling. The ''trans''-compound gives a colourless solution, from which snow-white needles of ''trans''-[Pt(tu)2(NH3)2]Cl2 deposit on coolin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Test
In chemistry, a chemical test is a qualitative or quantitative procedure designed to identify, quantify, or characterise a chemical compound or chemical group. Purposes Chemical testing might have a variety of purposes, such as to: * Determine if, or verify that, the requirements of a specification, regulation, or contract are met * Decide if a new product development program is on track: Demonstrate proof of concept * Demonstrate the utility of a proposed patent * Determine the interactions of a sample with other known substances * Determine the composition of a sample * Provide standard data for other scientific, medical, and Quality assurance functions * Validate suitability for end-use * Provide a basis for Technical communication * Provide a technical means of comparison of several options * Provide evidence in legal proceedings Biochemical tests * Clinistrips quantitatively test for sugar in urine * The Kastle-Meyer test tests for the presence of blood * Salicyla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cis Isomer
Cis or cis- may refer to: Places * Cis, Trentino, in Italy * In Poland: ** Cis, Świętokrzyskie Voivodeship, south-central ** Cis, Warmian-Masurian Voivodeship, north Math, science and biology * cis (mathematics) (cis(''θ'')), a trigonometric mathematical function related to Euler's formula * ''Cis'' (beetle), genus * Cis–trans isomerism, in chemistry * cis-regulatory element, regions of non-coding DNA which regulate the transcription of nearby genes Other uses * Cisgender, in contrast with transgender * C♯ (musical note), known as cis See also * CIS (other) * * Ciss (other) Ciss (pronounced SIHS) is a Senegalese surname. Notable people with the surname include: * Amadou Ciss (born 1999), Senegalese footballer who plays for Fortuna Sittard * Elhadji Ciss (born 1994), Senegalese footballer who plays for Sion *Khadija ... * Csi (other) {{disambiguation, geo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halogen
The halogens () are a group in the periodic table consisting of five or six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At), and tennessine (Ts). In the modern IUPAC nomenclature, this group is known as group 17. The word "halogen" means "salt former" (or "salt maker"). When halogens react with metals, they produce a wide range of salts, including calcium fluoride, sodium chloride (common table salt), silver bromide and potassium iodide. The group of halogens is the only periodic table group that contains elements in three of the main states of matter at standard temperature and pressure. All of the halogens form acids when bonded to hydrogen. Most halogens are typically produced from minerals or salts. The middle halogens—chlorine, bromine, and iodine—are often used as disinfectants. Organobromides are the most important class of flame retardants, while elemental halogens are dangerous and can be toxic. Hist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudohalide
Pseudohalogens are polyatomic analogues of halogens, whose chemistry, resembling that of the true halogens, allows them to substitute for halogens in several classes of chemical compounds. Pseudohalogens occur in pseudohalogen molecules, inorganic molecules of the general forms ''Ps''–''Ps'' or ''Ps''–X (where ''Ps'' is a pseudohalogen group), such as cyanogen; pseudohalide anions, such as cyanide ion; inorganic acids, such as hydrogen cyanide; as ligands in coordination complexes, such as ferouscyanide; and as functional groups in organic molecules, such as the nitrile group. Well-known pseudohalogen functional groups include cyanide, cyanate, thiocyanate, and azide. Common pseudohalogens and their nomenclature Many pseudohalogens are known by specialized common names according to where they occur in a compound. Well-known ones include (the true halogen chlorine is listed for comparison): Au− is considered to be a pseudohalogen ion due to its disproportionation reactio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiourea
Thiourea () is an organosulfur compound with the formula and the structure . It is structurally similar to urea (), except that the oxygen atom is replaced by a sulfur atom (as implied by the '' thio-'' prefix); however, the properties of urea and thiourea differ significantly. Thiourea is a reagent in organic synthesis. " Thioureas" refer to a broad class of compounds with the general structure . Thioureas are related to thioamides, e.g. , where R is methyl, ethyl, etc. Structure and bonding Thiourea is a planar molecule. The C=S bond distance is 1.71 Å. The C-N distances average 1.33 Å. The weakening of the C-S bond by C-N pi-bonding is indicated by the short C=S bond in thiobenzophenone, which is 1.63 Å. Thiourea occurs in two tautomeric forms, of which the thione form predominates in aqueous solutions. The equilibrium constant has been calculated as ''K''eq is . The thiol form, which is also known as an isothiourea, can be encountered in substituted compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cisplatin
Cisplatin is a chemotherapy medication used to treat a number of cancers. These include testicular cancer, ovarian cancer, cervical cancer, breast cancer, bladder cancer, head and neck cancer, esophageal cancer, lung cancer, mesothelioma, brain tumors and neuroblastoma. It is given by injection into a vein. Common side effects include bone marrow suppression, hearing problems, including total irreversible hearing loss, usually restricted to one ear, kidney damage, and vomiting. Other serious side effects include numbness, trouble walking, allergic reactions, electrolyte problems, and heart disease. Use during pregnancy can cause harm to the developing fetus. Cisplatin is in the platinum-based antineoplastic family of medications. It works in part by binding to DNA and inhibiting its replication. Cisplatin was discovered in 1845 and licensed for medical use in 1978 and 1979. It is on the World Health Organization's List of Essential Medicines. Medical use C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trans Effect
In inorganic chemistry, the trans effect is the increased lability of ligands that are trans to certain other ligands, which can thus be regarded as trans-directing ligands. It is attributed to electronic effects and it is most notable in square planar complexes, although it can also be observed for octahedral complexes.Coe, B. J.; Glenwright, S. J. Trans-effects in octahedral transition metal complexes. ''Coordination Chemistry Reviews'' 2000, ''203'', 5-80. The analogous cis effect is most often observed in octahedral transition metal complexes. In addition to this ''kinetic trans effect'', trans ligands also have an influence on the ground state of the molecule, the most notable ones being bond lengths and stability. Some authors prefer the term trans influence to distinguish it from the kinetic effect, while others use more specific terms such as structural trans effect or thermodynamic trans effect. The discovery of the trans effect is attributed to Ilya Ilich Chernyaev, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soviet Union
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a Federation, federal union of Republics of the Soviet Union, fifteen national republics; in practice, both Government of the Soviet Union, its government and Economy of the Soviet Union, its economy were highly Soviet-type economic planning, centralized until its final years. It was a one-party state governed by the Communist Party of the Soviet Union, with the city of Moscow serving as its capital as well as that of its largest and most populous republic: the Russian Soviet Federative Socialist Republic, Russian SFSR. Other major cities included Saint Petersburg, Leningrad (Russian SFSR), Kyiv, Kiev (Ukrainian Soviet Socialist Republic, Ukrainian SSR), Minsk (Byelorussian Soviet Socialist Republic, Byelorussian SSR), Tas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nikolai Kurnakov
Nikolai Semyonovich Kurnakov (russian: Николай Семёнович Курнаков; 6 December 1860 – 19 March 1941) was a Russian chemist, who is internationally recognized as the originator of physicochemical analysis. He also was one of the principal founders of the platinum industry in the Soviet Union. A chemical reaction that he pioneered, known as the Kurnakov test, is still used to differentiate cis from trans isomers of divalent platinum and is his best-known contribution to coordination chemistry. Early life and career Kurnakov was born in Nolinsk, Vyatka Governorate. He attended a high school at Nizhny Novgorod and later studied at the Mining Institute in St. Petersburg. Distantly related to organic chemist Vladimir Markovnikov, he made an early choice of a chemistry career, setting up a home laboratory at 14. He published his first article on alum crystallization and sodium thioantimoniate in 1882. In the same year he graduated as a mining engineer. Durin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
George B
George may refer to: People * George (given name) * George (surname) * George (singer), American-Canadian singer George Nozuka, known by the mononym George * George Washington, First President of the United States * George W. Bush, 43rd President of the United States * George H. W. Bush, 41st President of the United States * George V, King of Great Britain, Ireland, the British Dominions and Emperor of India from 1910-1936 * George VI, King of Great Britain, Ireland, the British Dominions and Emperor of India from 1936-1952 * Prince George of Wales * George Papagheorghe also known as Jorge / GEØRGE * George, stage name of Giorgio Moroder * George Harrison, an English musician and singer-songwriter Places South Africa * George, Western Cape ** George Airport United States * George, Iowa * George, Missouri * George, Washington * George County, Mississippi * George Air Force Base, a former U.S. Air Force base located in California Characters * George (Peppa Pig), a 2-year-old pig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transplatin
''trans''-Dichlorodiammineplatinum(II) is the trans isomer of the coordination complex with the formula ''trans''-PtCl2(NH3)2, sometimes called ''transplatin''. It is a yellow solid with low solubility in water but good solubility in DMF. The existence of two isomers of PtCl2(NH3)2 led Alfred Werner to propose square planar molecular geometry. It belongs to the molecular symmetry point group D2h. Preparation and reactions The complex is prepared by treating t(NH3)4l2 with hydrochloric acid. Many of the reactions of this complex can be explained by the trans effect. It slowly hydrolyzes in aqueous solution to give the mixed aquo complex ''trans''- tCl(H2O)(NH3)2l. Similarly it reacts with thiourea (tu) to give colorless ''trans''- t(tu)2(NH3)2l2. In contrast, the cis isomer gives t(tu)4l2. Oxidative addition of chlorine gives ''trans''-PtCl4(NH3)2. Medicinal chemistry ''trans''-Dichlorodiammineplatinum(II) has had far less impact on medicinal chemistry compared to its cis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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