chemical kinetics

Chemical reactors are vessels that are designed for a chemical reaction to occur inside of them. The design of a chemical reactor deals with multiple aspects of chemical engineering. It is the job of the chemical engineer to ensure that the reaction proceeds with the highest efficiency towards the desired output product, producing the highest yield of product while requiring the least amount of money to purchase and operate. Normal operating expenses include energy input, energy removal, raw material costs, etc. Energy changes can com ...

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In general, any time a chemical reaction occurs it is due to the chemical being able to enter a more stable[better] state. Quantum chemistry provides the most in depth and exact understanding of the reason this occurs. Electrons exist in orbitals that are the result of solving the Schrodinger equation for specific situations. All things (values of the n and ml quantum numbers) being equal, the order of stability of electrons in a system from least to greatest is unpaired with no other electrons in similar orbi ...

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Reactivity, Reactivity - Causes of reactivity, Reactivity - Chemical kinetics and reactivity

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In general, any time a chemical reaction occurs it is due to the chemical being able to enter a more stable state. Quantum chemistry provides the most in depth and exact understanding of the reason this occurs. Electrons exist in orbitals that are the result of solving the Schrodinger equation for specific situations. All things (values of the n and ml quantum numbers) being equal, the order of stability of electrons in a system from least to greatest is unpaired with no other electrons in similar orbitals, un ...

See also:

Reactivity, Reactivity - Causes of reactivity, Reactivity - Chemical kinetics and reactivity

Read more here: » Reactivity: Encyclopedia II - Reactivity - Causes of reactivity

A chemical reaction is a process that results in the interconversion of chemical substances [1]. The substance(s) initially involved in a chemical reaction are called reactants. Chemical reactions are characterized by a chemical change and it yields one or more product(s) which are different from the reactants. Classically, chemical reactions encompass changes that strictly involve the motion of electrons in the forming and breaking of chemical bond ...

Including:

• Chemical reaction - Reaction types
• Chemical reaction - Thermochemistry
• Chemical reaction - Chemical equilibrium
• Chemical reaction - Exothermic reactions
• Chemical reaction - Endothermic reactions
• Chemical reaction - Chemical kinetics

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Chemistry (derived from the Arabic word kimia, alchemy, where al is Arabic for the) is the science of matter that deals with the composition, structure, and properties of substances and with the transformations that they undergo. In the study of matter, chemistry also investigates its interactions with energy and itself (see physics, biology). Because of the diversity of matter, which is mostly composed of different combinations of atoms, chemists often study how atoms of different chemical elements interact to fo ...

Including:

• Chemistry - Introduction
• Chemistry - Chemical phenomena
• Chemistry - Subdisciplines of chemistry
• Chemistry - Fundamental concepts
• Chemistry - Chemical Laws
• Chemistry - History of chemistry
• Chemistry - Etymology

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The rate of any given reaction A → products (important point is that the order is first) is governed by the equation: Rate = k[A] where the rate is the number of moles per second consumed in the rate-determining step of the reaction, [A] is the concentration of the substance in moles per liter and k is the reaction constant which is constant for that temperature and pressure, though it is independent of concentration. The greater the reactivity of a com ...

See also:

Reactivity, Reactivity - Causes of reactivity, Reactivity - Chemical kinetics and reactivity

Read more here: » Reactivity: Encyclopedia II - Reactivity - Chemical kinetics and reactivity

See main article: Thermochemistry. Thermochemistry deciphers whether a specific chemical reaction can or cannot occur. Thermodynamics (or what is now known as equilibrium thermodynamics) understands the reaction in terms of the initial and final states of the reaction mixture. Reactions very seldom occur directly. Usually, reactants must collide to form an activated complex. This complex has a higher internal energy than the original reactants combined, having gained some from the kinetic energy of the reactant substance ...

See also:

Chemical reaction, Chemical reaction - Reaction types, Chemical reaction - Thermochemistry, Chemical reaction - Chemical equilibrium, Chemical reaction - Exothermic reactions, Chemical reaction - Endothermic reactions, Chemical reaction - Chemical kinetics

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A collision between reactant molecules may or may not result in a successful reaction. The outcome depends on factors such as the relative kinetic energy, relative orientation and internal energy of the molecules. Even if the collision partners form an activated complex they are not bound to go on and form products, and instead the complex may fall apart back to the reactants. ...

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Transition state, Transition state - Introduction, Transition state - History, Transition state - Problems in observing transition states, Transition state - Locating Transition States by Computational Chemistry, Transition state - The Hammond-Leffler postulate, Transition state - Implications for enzymatic catalysis

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Nomenclature Main article: IUPAC nomenclature Nomenclature refers to the system for naming chemical compounds. There are well-defined systems in place for naming chemical species. Organic compounds are named according to the organic nomenclature system. Inorganic compounds are named according to the inorganic nomenclature system. Atoms Main article: Atom An atom is a collection of matter consisting of a positively charged core (the atomic nucleus) which contains protons and neutrons, and which maintains a number of electrons to balance the posi ...

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Chemistry, Chemistry - Introduction, Chemistry - Chemical phenomena, Chemistry - Subdisciplines of chemistry, Chemistry - Fundamental concepts, Chemistry - History of chemistry, Chemistry - Etymology

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There are certain implications of the equilibrium constant. If the value is very large, over 1, the reaction is said to lie to the right (of the arrow) indicating a greater concentration of products; values less than 1 lie to the left higher formation rates of reactants, and values of one indicate equal concentrations. Knowledge of the equilibrium constant can help us determine, in an industrial setting f ...

See also:

Equilibrium constant, Equilibrium constant - Reaction conditions, Equilibrium constant - Applications, Equilibrium constant - Sources

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Michael was born into a Jewish family in Budapest. His older brother Karl become a famous economist. Their father was an engineer and entrepreneur whose volatile fortunes in railway speculation motivated Polanyi to seek financial stability through a career in medicine. He graduated in 1913, and shortly afterwards served as a physician in the Austro-Hungarian army during World War I, but was hospitalised, and during his convalescence wrote what became a doctorate in physical chem ...

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Michael Polanyi, Michael Polanyi - Early life, Michael Polanyi - Physical chemistry, Michael Polanyi - Philosophy of science, Michael Polanyi - Economics, Michael Polanyi - Honours, Michael Polanyi - Knowledge, Michael Polanyi - Bibliography

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Base catalysed phenol formaldehyde resins are made with a formaldehyde to phenol ratio of greater than one (usually around 1.5). Phenol, formaldehyde, water and catalyst are mixed in the desired amount, depending on the resin to be formed, and are then heated. The first part of the reaction, at around 70 °C, forms hydroxymethyl phenols. This results in a thick reddish-brown goo, the resin. The rate of the base catalysed reaction initially increases with pH, and reaches a maximum at approx. pH = 10. The reactive species is the phenoli ...

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Phenol formaldehyde resin, Phenol formaldehyde resin - Acid catalysed, Phenol formaldehyde resin - Base catalysed, Phenol formaldehyde resin - Crosslinking and the phenol/formaldehyde ratio

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The fundamental component of chemistry is that it involves matter in some way (this explains its broad reach). It may involve the interaction of matter with non-material phenomena such as energy. More central to chemistry is the interaction of one substance with another such as in the classic chemical reaction where one substance is transformed into another; or with electromagnetic radiation (as in photochemistry). The class of scientists who profess chemistry are known as chemists. According to the contemporary chemistry, almost all ...

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Chemistry, Chemistry - Introduction, Chemistry - Chemical phenomena, Chemistry - Subdisciplines of chemistry, Chemistry - Fundamental concepts, Chemistry - Chemical Laws, Chemistry - History of chemistry, Chemistry - Etymology

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Two elementary methods are discussed to give the reader a feeling for the subject. After that, pointers are provided to other methods (which are generally more accurate and efficient). The methods mentioned here are analysed in the next section. Numerical ordinary differential equations - The Euler method. For more details on this topic, see Euler integration. Starting with the differential equation (1), we replace the derivative y' by the finite difference approximation < ...

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Numerical ordinary differential equations, Numerical ordinary differential equations - The problem, Numerical ordinary differential equations - Methods, Numerical ordinary differential equations - The Euler method, Numerical ordinary differential equations - The backward Euler method, Numerical ordinary differential equations - Generalisations, Numerical ordinary differential equations - Advanced features, Numerical ordinary differential equations - Alternative methods, Numerical ordinary differential equations - Analysis, Numerical ordinary differential equations - Convergence, Numerical ordinary differential equations - Order, Numerical ordinary differential equations - Stability and stiffness, Numerical ordinary differential equations - History

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At its origins, thermodynamics was the study of engines. Prior to 1698 and the invention of the Savery Engine, horses were used to power pulleys, attached to buckets, which lifted water out of flooded salt mines in England. In the years to follow, more variations of steam engines were built, such as the Newcomen Engine, and later the Watt Engine. In time, these early engines would eventually be utilized in place of horses. Thus, each engine began to be associated with a certain amount of "horse power" depending upon how many horses it had re ...

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History of thermodynamics, History of thermodynamics - Contributions from antiquity, History of thermodynamics - Transition from alchemy to chemistry, History of thermodynamics - Modern Theory, History of thermodynamics - Kinetic theory, History of thermodynamics - Conservation of energy, History of thermodynamics - Entropy and the second law, History of thermodynamics - Phenomenological thermodynamics, History of thermodynamics - Gas laws, History of thermodynamics - Heat transfer, History of thermodynamics - Cryogenics

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Before receiving his doctorate, Van 't Hoff had already published the first of his important contributions to organic chemistry. In 1874 he accounted for the phenomenon of optical activity by assuming that the chemical bonds between carbon atoms and their neighbors were directed towards the corners of a regular tetrahedron. This three-dimensional structure perfectly accounted for the isomers found in nature (stereochemistry). He shares credit for thi ...

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Jacobus Henricus van 't Hoff, Jacobus Henricus van 't Hoff - Early days, Jacobus Henricus van 't Hoff - Contributions to chemistry and major works, Jacobus Henricus van 't Hoff - Winner of the inaugural Nobel Prize in chemistry, Jacobus Henricus van 't Hoff - Final days awards and legacy

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There are five major classifications of chemical reactions. Some common and widely used terms are: Isomerization in which a chemical compound undergoes a structural rearrangement without any change in its net atomic composition; see stereoisomerism Direct combination or synthesis, in which two or more chemical elements or compounds unite to form a more complex product: 2H2 (g) + O2 (g) → 2H2O (l) Chemical decomposition or an ...

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Chemical reaction, Chemical reaction - Reaction types, Chemical reaction - Thermochemistry, Chemical reaction - Chemical equilibrium, Chemical reaction - Exothermic reactions, Chemical reaction - Endothermic reactions, Chemical reaction - Chemical kinetics

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Numerical analysis is not only the design of numerical methods, but also their analysis. Three central concepts in this analysis are convergence (whether the method approximates the solution), order (how well it approximates the solution), and stability (whether errors are damped out). Numerical ordinary differential equations - Convergence. A numerical method is said to be convergent if the numerical solution approaches the exact solution as the step size h goes to 0. More precisely, we require that for every ODE (1) with a Lipschitz function f ...

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Numerical ordinary differential equations, Numerical ordinary differential equations - The problem, Numerical ordinary differential equations - Methods, Numerical ordinary differential equations - The Euler method, Numerical ordinary differential equations - The backward Euler method, Numerical ordinary differential equations - Generalisations, Numerical ordinary differential equations - Advanced features, Numerical ordinary differential equations - Alternative methods, Numerical ordinary differential equations - Analysis, Numerical ordinary differential equations - Convergence, Numerical ordinary differential equations - Order, Numerical ordinary differential equations - Stability and stiffness, Numerical ordinary differential equations - History

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Main article: Etymology of chemistry The Etymology of the word chemistry goes back to the old French alkemie; or the Arabic al-kimia: the art of transformation. ...

See also:

Chemistry, Chemistry - Introduction, Chemistry - Chemical phenomena, Chemistry - Subdisciplines of chemistry, Chemistry - Fundamental concepts, Chemistry - History of chemistry, Chemistry - Etymology

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In 1885 he was appointed member of the Royal Netherlands Academy of Sciences. Other distinctions included the honorary doctorates of Harvard and Yale 1901, Victoria University, Manchester 1903, Heidelberg 1908; the Davy Medal of the Royal Society 1893 (along with Le Bel), Helmholtz Medal of the Prussian Academy of Sciences 1911; he was also appointed Chevalier de la Legion d'Honneur 1894, Senator der Kaiser-Wilhelm-Gesellschaft (1911). Van't Hoff was also honorary member of the British Chemical Society in London, the Royal Academy of Sciences, in Gottingen 1892, A ...

See also:

Jacobus Henricus van 't Hoff, Jacobus Henricus van 't Hoff - Early days, Jacobus Henricus van 't Hoff - Contributions to chemistry and major works, Jacobus Henricus van 't Hoff - Winner of the inaugural Nobel Prize in chemistry, Jacobus Henricus van 't Hoff - Final days awards and legacy

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