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Belousov–Zhabotinsky Reaction
A Belousov–Zhabotinsky reaction, or BZ reaction, is one of a class of reactions that serve as a classical example of non-equilibrium thermodynamics, resulting in the establishment of a nonlinear chemical oscillator. The only common element in these oscillators is the inclusion of bromine and an acid. The reactions are important to theoretical chemistry in that they show that chemical reactions do not have to be dominated by equilibrium thermodynamic behavior. These reactions are far from equilibrium and remain so for a significant length of time and evolve chaotically. In this sense, they provide an interesting chemical model of nonequilibrium biological phenomena; as such, mathematical models and simulations of the BZ reactions themselves are of theoretical interest, showing phenomenon as noise-induced order. An essential aspect of the BZ reaction is its so called "excitability"; under the influence of stimuli, patterns develop in what would otherwise be a perfectly quies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Belousov-Zhabotinsky Reaction
''The'' () is a grammatical article in English, denoting persons or things already mentioned, under discussion, implied or otherwise presumed familiar to listeners, readers, or speakers. It is the definite article in English. ''The'' is the most frequently used word in the English language; studies and analyses of texts have found it to account for seven percent of all printed English-language words. It is derived from gendered articles in Old English which combined in Middle English and now has a single form used with pronouns of any gender. The word can be used with both singular and plural nouns, and with a noun that starts with any letter. This is different from many other languages, which have different forms of the definite article for different genders or numbers. Pronunciation In most dialects, "the" is pronounced as (with the voiced dental fricative followed by a schwa) when followed by a consonant sound, and as (homophone of pronoun '' thee'') when followed by a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerium(IV) Sulfate
Cerium(IV) sulfate, also called ceric sulfate, is an inorganic compound. It exists as the anhydrous salt Ce( SO4)2 as well as a few hydrated forms: Ce(SO4)2(H2O)x, with x equal to 4, 8, or 12. These salts are yellow to yellow/orange solids that are moderately soluble in water and dilute acids. Its neutral solutions slowly decompose, depositing the light yellow oxide CeO2. Solutions of ceric sulfate have a strong yellow color. The tetrahydrate loses water when heated to 180-200 °C. It is insoluble in glacial acetic acid and pure (96%) ethanol. It was historically produced by direct reaction of fine, calcined cerium (IV) oxide and concentrated sulfuric acid, yielding the tetrahydrate. Uses The ceric ion is a strong oxidizer, especially under acidic conditions. If ceric sulfate is added to dilute hydrochloric acid, then elemental chlorine is formed, albeit slowly. With stronger reducing agents it reacts much faster. For example, with sulfite in acidic environments it react ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petri Dish
A Petri dish (alternatively known as a Petri plate or cell-culture dish) is a shallow transparent lidded dish that biologists use to hold growth medium in which cells can be cultured,R. C. Dubey (2014): ''A Textbook Of Biotechnology For Class-XI'', 4th edition, p. 469. originally, cells of bacteria, fungi and small mosses. The container is named after its inventor, German bacteriologist Julius Richard Petri. It is the most common type of culture plate. The Petri dish is one of the most common items in biology laboratories and has entered popular culture. The term is sometimes written in lower case, especially in non-technical literature. What was later called Petri dish was originally developed by German physician Robert Koch in his private laboratory in 1881, as a precursor method. Petri, as assistant to Koch, at Berlin University made the final modifications in 1887 as used today. Penicillin, the first antibiotic, was discovered in 1929 when Alexander Fleming noticed that m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Redox Indicator
A redox indicator (also called an oxidation-reduction indicator) is an indicator which undergoes a definite color change at a specific electrode potential. The requirement for fast and reversible color change means that the oxidation-reduction equilibrium for an indicator redox system needs to be established very quickly. Therefore, only a few classes of organic redox systems can be used for indicator purposes. There are two common classes of redox indicators: * metal complexes of phenanthroline and bipyridine. In these systems, the metal changes oxidation state. * organic redox systems such as methylene blue. In these systems, a proton participant in the redox reaction. Therefore, sometimes redox indicators are also divided into two general groups: independent or dependent on pH. The most common redox indicator are organic compounds. Redox Indicator example: The molecule 2,2'- Bipyridine is a redox Indicator. In solution, it changes from light blue to red at an electrode po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in front of oxygen (32.1% and 30.1%, respectively), forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust. In its metallic state, iron is rare in the Earth's crust, limited mainly to deposition by meteorites. Iron ores, by contrast, are among the most abundant in the Earth's crust, although extracting usable metal from them requires kilns or furnaces capable of reaching or higher, about higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BCE and the use of iron tools and weapons began to displace copper alloys, in some regions, only around 1200 BCE. That event is considered the transition from the Bronze Age to the Iron A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenanthroline
1,10-Phenanthroline (phen) is a heterocyclic organic compound. It is a white solid that is soluble in organic solvents. The 1,10 refer to the location of the nitrogen atoms that replace CH's in the hydrocarbon called phenanthrene. Abbreviated "phen", it is used as a ligand in coordination chemistry, forming strong complexes with most metal ions.Luman, C.R. and Castellano, F.N. (2003) "Phenanthroline Ligands" in Comprehensive Coordination Chemistry II. Elsevier. . It is often sold as the monohydrate. Synthesis Phenanthroline may be prepared by two successive Skraup reactions of glycerol with ''o''-phenylenediamine, catalyzed by sulfuric acid, and an oxidizing agent, traditionally aqueous arsenic acid or nitrobenzene. Dehydration of glycerol gives acrolein which condenses with the amine followed by a cyclization. Coordination chemistry In terms of its coordination properties, phenanthroline is similar to 2,2'-bipyridine (bipy) with the advantage that the two nitrogen donors ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Complex (chemistry)
A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many metal-containing compounds, especially those that include transition metals (elements like titanium that belong to the Periodic Table's d-block), are coordination complexes. Nomenclature and terminology Coordination complexes are so pervasive that their structures and reactions are described in many ways, sometimes confusingly. The atom within a ligand that is bonded to the central metal atom or ion is called the donor atom. In a typical complex, a metal ion is bonded to several donor atoms, which can be the same or different. A polydentate (multiple bonded) ligand is a molecule or ion that bonds to the central atom through several of the ligand's atoms; ligands with 2, 3, 4 or even 6 bonds to the central atom are common. These compl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferroin
Ferroin is the chemical compound with the formula e(''o''-phen)3O4, where ''o''-phen is an abbreviation for 1,10-phenanthroline, a bidentate ligand. The term "ferroin" is used loosely and includes salts of other anions such as chloride. Redox indicator This coordination compound is used as an indicator in analytical chemistry. The active ingredient is the e(''o''-phen)3sup>2+ ion, which is a chromophore that can be oxidized to the ferric derivative e(''o''-phen)3sup>3+. The potential for this redox change is +1.06 volts in 1 M H2SO4. It is a popular redox indicator for visualizing oscillatory Belousov–Zhabotinsky reactions. Ferroin is suitable as a redox indicator, as the color change is reversible, very pronounced and rapid, and the ferroin solution is stable up to 60 °C. It is the main indicator used in cerimetry.{{cite book, title=Handbook on the Physics and Chemistry of Rare Earths, url=https://books.google.com/books?id=_Ro3Fqtz4xgC&pg=PA289, date= 2006, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prague
Prague ( ; cs, Praha ; german: Prag, ; la, Praga) is the capital and largest city in the Czech Republic, and the historical capital of Bohemia. On the Vltava river, Prague is home to about 1.3 million people. The city has a temperate oceanic climate, with relatively warm summers and chilly winters. Prague is a political, cultural, and economic hub of central Europe, with a rich history and Romanesque, Gothic, Renaissance and Baroque architectures. It was the capital of the Kingdom of Bohemia and residence of several Holy Roman Emperors, most notably Charles IV (r. 1346–1378). It was an important city to the Habsburg monarchy and Austro-Hungarian Empire. The city played major roles in the Bohemian and the Protestant Reformations, the Thirty Years' War and in 20th-century history as the capital of Czechoslovakia between the World Wars and the post-war Communist era. Prague is home to a number of well-known cultural attractions, many of which survived the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anatol Zhabotinsky
Anatol Markovich Zhabotinsky (Анато́лий Ма́ркович Жаботи́нский) (January 17, 1938 – September 16, 2008) was a Soviet biophysicist who created a theory of the chemical clock known as Belousov–Zhabotinsky reaction in the 1960s and published a comprehensive body of experimental data on chemical wave propagation and pattern formation in nonuniform media. The reaction had been discovered by Boris Pavlovich Belousov in the early 1950s. From 1991 until his death, Zhabotinsky was an Adjunct Professor of Chemistry at Brandeis University in Waltham, Massachusetts. References * External links Zhabotinsky pageat Brandeis {{DEFAULTSORT:Zhabotinsky, Anatol Markovich 1938 births 2008 deaths Russian Jews Jewish scientists Russian physicists 20th-century American physicists Moscow Institute of Physics and Technology faculty Lenin Prize winners Soviet Jews Soviet biophysicists ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Simon El'evich Shnoll
Simon El'evich Shnol (russian: Симон Эльевич Шноль; 21 March 1930 – 11 September 2021) was a biophysicist, and a historian of Soviet science. He was a professor at Physics Department of Moscow State University and a member of Russian Academy of Natural Sciences. His fields of interest were the oscillatory processes in biology, the theory of evolution, chronobiology, and the history of science. He had mentored many successful scientists, including Anatoly Zhabotinsky. Biography Simon Shnoll was born in Moscow in 1930. His father was Eli Gershevich Shnol, a linguist and philosopher. His mother was Faina Yakovlevna Yudovich, a teacher of Russian language and literature. In 1946, he was enrolled to Moscow State University (MSU). After graduation, he was engaged in developing new methods for using radioactive isotopes in medicine, in the Central Institute for Improvement of Medicine in Moscow, where he worked until 1959. In 1960 he went to work at MSU. Since 197 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Chemical Education
The ''Journal of Chemical Education'' is a monthly peer-reviewed academic journal available in both print and electronic versions. It is published by the Division of Chemical Education of the American Chemical Society and was established in 1924 by Neil Gordon. The journal covers research on chemical education Chemistry education (or chemical education) is the study of teaching and learning chemistry. It is one subset of STEM education or discipline-based education research (DBER). Topics in chemistry education include understanding how students learn ..., and its target audience includes instructors of chemistry from middle school through graduate school and some scientists in commerce, industry, and government. References External links * Chemical education journals American Chemical Society academic journals Monthly journals Publications established in 1924 English-language journals {{chemistry-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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