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Molecular reactions

In this reaction I" is the nucleophile, and Br" is called the leaving group (or nucleofuge). Beyond this, the classification symbolism may include a designation of the molecularity of the reaction. Molecularity is the number of reactant molecules included in the transition state. The above reaction is an 8 2 reaction, because both reactants are present in the transition state. On the other hand, this substitution... [Pg.9]

If one of the reactants is the solvent, this reactant is present in large excess, so its kinetic participation will not be observed. Thus a bimolecular hydrolysis reaction commonly follows first-order kinetics. This example shows that the reaction order may not be equal to the reaction molecularity. [Pg.24]

Radiolytic ethylene destruction occurs with a yield of ca. 20 molecules consumed/100 e.v. (36, 48). Products containing up to six carbons account for ca. 60% of that amount, and can be ascribed to free radical reactions, molecular detachments, and low order ion-molecule reactions (32). This leaves only eight molecules/100 e.v. which may have formed ethylene polymer, corresponding to a chain length of only 2.1 molecules/ ion. Even if we assumed that ethylene destruction were entirely the result of ionic polymerization, only about five ethylene molecules would be involved per ion pair. The absence of ionic polymerization can also be demonstrated by the results of the gamma ray initiated polymerization of ethylene, whose kinetics can be completely explained on the basis of conventional free radical reactions and known rate constants for these processes (32). An increase above the expected rates occurs only at pressures in excess of ca. 20 atmospheres (10). The virtual absence of ionic polymerization can be regarded as one of the most surprising aspects of the radiation chemistry of ethylene. [Pg.266]

Figure 28-11. The prolyl hydroxylase reaction. The substrate is a proline-rich peptide. During the course of the reaction, molecular oxygen is incorporated into both succinate and proline. Lysyl hydroxylase catalyzes an analogous reaction. Figure 28-11. The prolyl hydroxylase reaction. The substrate is a proline-rich peptide. During the course of the reaction, molecular oxygen is incorporated into both succinate and proline. Lysyl hydroxylase catalyzes an analogous reaction.
Amidation is particularly well adapted to use as a polymer-forming condensation reaction. The reaction is rapid above 180° to 200°C, it is remarkably free from side reactions, no catalysts are required (indeed, none are known), and the process is of the second order so that the molecular weight increases directly as the time of reaction. Molecular weights of 20,000 to 30,000 are attainable with no great difficulty under favorable conditions. This is not true of particular polyamide reactants susceptible to side reactions, as, for example, in the reaction of a diamine with glutaric acid wherein the inherent instability of the glutaric amide unit leads to decomposition. [Pg.94]

In situ infrared spectroscopy allows one to obtain stracture-specific information at the electrode-solution interface. It is particularly useful in the study of electrocat-alytic reactions, molecular adsorption, and the adsorption of ions at metal surfaces. [Pg.505]

The Flory principle is one of two assumptions underlying an ideal kinetic model of any process of the synthesis or chemical modification of polymers. The second assumption is associated with ignoring any reactions between reactive centers belonging to one and the same molecule. Clearly, in the absence of such intramolecular reactions, molecular graphs of all the components of a reaction system will contain no cycles. The last affirmation concerns sol molecules only. As for the gel the cyclization reaction between reactive centers of a polymer network is quite admissible in the framework of an ideal model. [Pg.170]

The number of chemical species involved in a single elementary reaction is referred to as the molecularity of that reaction. Molecularity is a theoretical concept, whereas stoichiometry and order are empirical concepts. A simple reaction is referred to as uni-, bi-, or termolecular if one, two, or three species, respectively, participate as reactants. The majority of known elementary steps are bimolecular, with the balance being unimolecular and termolecular. [Pg.77]

Any bond can break at any time Almost no monomer produced except at the end of the reaction Molecular mass decreases rapidly... [Pg.59]

Longuet-Higgins phase-based treatment, three-particle reactive system, 157-168 theoretical background, 43-44 observability, 208 quantum theory, 200 Phase-inverting reactions molecular model, 496-499 phase-change rule, pericyclic reactions, 449-450... [Pg.92]

These reactions produce free radicals, as follows from the fact of consumption of free radical acceptor [42]. The oxidation of ethylbenzene in the presence of thiophenol is accompanied by CL induced by peroxyl radicals of ethylbenzene [43]. Dilauryl dithiopropionate induces the pro-oxidative effect in the oxidation of cumene in the presence of cumyl hydroperoxide [44] provided that the latter is added at a sufficiently high proportion ([sulfide]/[ROOH] > 2). By analogy with similar systems, it can be suggested that sulfide should react with ROOH both heterolytically (the major reaction) and homolytically producing free radicals. When dilauryl dithiopropionate reacts with cumyl hydroperoxide in chlorobenzene, the rate constants of these reactions (molecular m and homolytic i) in chlorobenzene are [42]... [Pg.602]

Supercritical water (SCW) presents a unique combination of aqueous and non-aqueous character, thus being able to replace an organic solvent in certain kinds of chemical synthesis. In order to allow for a better understanding of the particular properties of SCW and of its influence on the rate of chemical reactions, molecular dynamics computer simulations were used to determine the free energy of the SN2 substitution reaction of Cl- and CH3C1 in SCW as a function of the reaction coordinate [216]. The free energy surface of this reaction was compared with that for the gas-phase and ambient water (AW) [248], In the gas phase, an ion-dipole complex and a symmetric transition... [Pg.344]

Figure 4.20 MTG/MTO reaction path and aromatics distribution with different zeolites as catalysts. (Reprinted from C.D. Chang, W.H. Lang, W.K. Bell, Catalysis in Organic Reactions, Molecular Shape-Selective Catalysis in Zeolites, pp. 93-94. Copyright 1981. With permission from Marcel Dekker.)... Figure 4.20 MTG/MTO reaction path and aromatics distribution with different zeolites as catalysts. (Reprinted from C.D. Chang, W.H. Lang, W.K. Bell, Catalysis in Organic Reactions, Molecular Shape-Selective Catalysis in Zeolites, pp. 93-94. Copyright 1981. With permission from Marcel Dekker.)...
The method is thus identical to the one described for gas-phase reactions. Thus, the activation energies of the forward and reverse reactions can be obtained at a temperature T from either simple or modified Arrhenius plots, and their difference is equal to the reaction enthalpy at the same temperature. Note, however, that equation 3.39 is valid for any elementary reaction in solution, whatever the molec-ularity, whereas in the case of gas-phase reactions, the equivalent expression depends on the reaction molecularity (see equations 3.19 and 3.22). [Pg.44]

The network consists of a train of molecular condensation reactions occurring in the gas phase delivering reactive intermediates that form in homogeneous reaction molecular species with low reactivity for CVD (PAH) and soot depositing loosely on the... [Pg.263]

Following the early studies on the pure interface, chemical and electrochemical processes at the interface between two immiscible liquids have been studied using the molecular dynamics method. The most important processes for electrochemical research involve charge transfer reactions. Molecular dynamics computer simulations have been used to study the rate and the mechanism of ion transfer across the water/1,2-dichloroethane interface and of ion transfer across a simple model of a liquid/liquid interface, where a direct comparison of the rate with the prediction of simple diffusion models has been made. ° ° Charge transfer of several types has also been studied, including the calculations of free energy curves for electron transfer reactions at a model liquid/liquid... [Pg.171]

GAS-SURFACE REACTIONS MOLECULAR DYNAMICS SIMULATIONS OF REAL SYSTEMS ... [Pg.281]

GAS-sintFACE Reactions Molecular Dynamics Simirations of Real Systems 281... [Pg.393]

Liquid-crystalline media are important especially for technical and biomedical applications of electron-transfer reactions. Molecular electronic systems, photosynthetic processes, and some... [Pg.306]

Rate expression Reaction order Probable reaction Molecularity... [Pg.173]

The basic theories of physics - classical mechanics and electromagnetism, relativity theory, quantum mechanics, statistical mechanics, quantum electrodynamics - support the theoretical apparatus which is used in molecular sciences. Quantum mechanics plays a particular role in theoretical chemistry, providing the basis for the valence theories which allow to interpret the structure of molecules and for the spectroscopic models employed in the determination of structural information from spectral patterns. Indeed, Quantum Chemistry often appears synonymous with Theoretical Chemistry it will, therefore, constitute a major part of this book series. However, the scope of the series will also include other areas of theoretical chemistry, such as mathematical chemistry (which involves the use of algebra and topology in the analysis of molecular structures and reactions) molecular mechanics, molecular dynamics and chemical thermodynamics, which play an important role in rationalizing the geometric and electronic structures of molecular assemblies and polymers, clusters and crystals surface, interface, solvent and solid-state effects excited-state dynamics, reactive collisions, and chemical reactions. [Pg.428]

V = V max [S]// m- A reaction of higher order is called pseudo-first-order if all but one of the reactants are high in concentration and do not change appreciably in concentration over the time course of the reaction. In such cases, these concentrations can be treated as constants. See Order of Reaction Half-Life Second-Order Reaction Zero-Order Reaction Molecularity Michaelis-Menten Equation Chemical Kinetics... [Pg.282]

Another example of zero-order kinetics is the rate of dissolution of encapsulated solutes restricted in the egress by passage through a small orifice in the capsule. If a soluble salt is added in addition to the encapsulated solute, one obtains an osmotically driven solute release system. See also Order of Reaction Molecularity Michaelis-Menten Equation Eirst-Order Reaction... [Pg.713]

SECOND-ORDER REACTION ZERO-ORDER REACTION MOLECULARITY... [Pg.743]

UNIMOLECULAR BIMOLECULAR TRANSITION-STATE THEORY ELEMENTARY REACTION MOLECULAR MECHANICS CALCULATIONS MOLECULAR ORBITALS MOLECULAR REARRANGEMENT MOLECULAR SIMILARITY Molecular stoichiometry of an elementary reaction,... [Pg.763]

ORDER OF REACTION MOLECULARITY CHEMICAL KINETICS FIRST-ORDER REACTIONS RATE CONSTANTS... [Pg.767]

CHEMICAL KINETICS RATE SATURATION MICHAELIS-MENTEN EQUATION ZERO-ORDER REACTIONS ORDER OF REACTION MOLECULARITY... [Pg.788]

Mechanisms in Organic Reactions Molecular Interactions Bioinorganic Chemistry Nucleic Acids... [Pg.192]


See other pages where Molecular reactions is mentioned: [Pg.198]    [Pg.374]    [Pg.47]    [Pg.387]    [Pg.258]    [Pg.44]    [Pg.444]    [Pg.913]    [Pg.87]    [Pg.62]    [Pg.169]    [Pg.203]    [Pg.209]    [Pg.719]    [Pg.394]    [Pg.50]    [Pg.230]   
See also in sourсe #XX -- [ Pg.7 ]




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1,3-Butadiene, 1,2-addition reactions molecular orbitals

1.3- Dipolar cycloaddition reactions frontier molecular orbital theory

1.3- dipolar cycloaddition reactions molecular orbitals

A tt Molecular Orbital Analysis of the Diels-Alder Reaction

Acid molecular sieves, reactions

Aldol condensation reaction molecular modeling

Anionic reactions, molecular

Anionic reactions, molecular rearrangements

Aqueous ionic reactions molecular equations

Behaviour of molecular pairs in homogeneous reaction

Bi-molecular reaction

Carbon-molecular oxygen reaction

Carbon-molecular oxygen reaction Subject

Carbon-molecular oxygen reaction intermediate stages

Carbon-molecular oxygen reaction rate equations

Carbon-molecular oxygen reaction spaces

Chemical Reaction, an Extremely Fast Process at Molecular Level

Chemical reaction molecular electron density changes

Chemical reaction molecularity

Chemical reactions molecular collisions, frequency

Chemical reactions molecular dynamics

Chemical reactions molecular level

Constructing Molecular Complexity and Diversity by Cycloaddition Reactions of Fulvenes

Coordinated molecular oxygen, reactions

Cross-molecular reactions

Diels-Alder reaction frontier molecular

Diels-Alder reaction molecular orbital considerations

Diels-Alder reaction molecular orbital diagram

Diels-Alder reactions in molecular cavities

Diels-Alder reactions molecular sieves

Diels-Alder reactions unoccupied molecular orbital

Direct molecular dynamics reaction

Electron-exchange reactions molecular dynamics

Electron/molecular reaction

Electrophilic addition reactions molecular vs ionic mechanism

Elementary reaction molecularity

From molecular potential energy to rates of reaction

Frontier Molecular Orbital Theory radical reactions

Frontier Molecular Orbital theory, for Diels-Alder reactions

Frontier molecular orbital theory reactions

Gaseous reaction kinetics and molecular decomposition

Highest occupied molecular orbital HOMO), pericyclic reaction

Highest occupied molecular orbital cycloaddition reactions and

Highest occupied molecular orbital electrocyclic reactions and

Highest occupied molecular orbital reactions

Hydrocarbon hydrogenation, molecular reaction model

Hydrocarbon pyrolysis, molecular reaction

Hydrocarbon pyrolysis, molecular reaction model

Hydrogen molecular exchange reaction

Hydrogen molecular, reaction with

Hydrogen molecular, reaction with ruthenium complexes

I Molecular diffusion and reaction rates

Influence of Molecular Interaction on Thermal Reaction Power

Intra-Molecular y-Hydroxy Oxime Formation (Barton Nitrite Ester Reaction)

Iodine, reaction with singlet molecular

Ion-molecular reactions

Ionization reactions molecular dynamics

Kinetics of Interfacial Reactions and Molecular Characterization

Lowest unoccupied molecular orbital LUMO), pericyclic reaction

Lowest unoccupied molecular orbital cycloaddition reactions and

Lowest unoccupied molecular orbital reactions

Maillard reaction molecular weight

Metals coordinated molecular, reactions

Metastable molecular hydrogen reactions

Methyl radical reaction with molecular oxygen

Molecular Beam Photoinduced Reactions

Molecular Design Limited Reactions Databases

Molecular Diels-Alder reaction

Molecular Diffusion Plus Convection and Chemical Reaction

Molecular Encapsulation: Organic Reactions in Constrained Systems Edited by Udo H. Brinker and Jean-Luc Mieusset

Molecular Encapsulation: Organic Reactions in Constrained Systems Edited by Udo H. Brinker and Jean-Luc Mieusset 2010 John Wiley Sons, Ltd

Molecular Mechanics Studies of Reactions

Molecular Orbital (MO) approach to acid-base reactions

Molecular Orbital Analysis of the Diels-Alder Reaction

Molecular Orbitals and Organic Chemical Reactions: Reference Edition Ian Fleming

Molecular Orbitals and Organic Chemical Reactions: Reference Edition Ian Fleming 2010 John Wiley Sons, Ltd

Molecular Orbitals and Organic Chemical Reactions: Student Edition Ian Fleming

Molecular Orbitals and Organic Chemical Reactions: Student Edition Ian Fleming 2009 John Wiley Sons, Ltd

Molecular Orbitals and Pericyclic Reactions of Conjugated Pi Systems

Molecular Phase Space Nonstatistical Effects in Reaction Dynamics

Molecular Radicals Radical Reactions

Molecular Reaction Dynamics (Femtochemistry)

Molecular Reactions Cyclic Transition States

Molecular Simulations Applied to Adsorption on and Reaction with Carbon

Molecular Vibrations and the Reaction Coordinate

Molecular absorption spectroscopy photosynthetic reaction center

Molecular activation high temperature reaction

Molecular activation microwave reactions

Molecular catalysts, multielectron reaction

Molecular characterization, reactions

Molecular characterization, reactions electrodes

Molecular complexation reactions

Molecular depiction precipitation reaction

Molecular diffusion and reaction rate

Molecular diminishing reaction

Molecular dynamics systems, chemical reaction efficiency

Molecular dynamics unimolecular reaction rate theory

Molecular electron-transfer reactions

Molecular elementary reaction rate data

Molecular elimination reactions

Molecular elimination reactions hydrocarbons

Molecular energy storage reactions

Molecular enlargement reactions

Molecular equation for acid-base reactions

Molecular extrusion reactions

Molecular ligand exchange reactions

Molecular mass, determination reaction, step

Molecular mechanics reactions

Molecular microkinetics simulations reaction

Molecular modelling, chemical reaction

Molecular orbital calculations bimolecular reactions

Molecular orbital theory chemical reactions

Molecular orbital theory, pericyclic reaction analysis

Molecular orbitals cycloaddition reactions

Molecular orbitals reaction rates

Molecular orbitals second-order reactions

Molecular orbitals symmetry-allowed reactions

Molecular orbitals zero-order reactions

Molecular orbitals, Diels-Alder reactions

Molecular oxygen, reaction drug substance with

Molecular probes polymerase chain reaction

Molecular proton detector, reaction

Molecular proton transfer reactions with

Molecular reaction dynamics

Molecular reaction models

Molecular reaction schemes

Molecular reaction vessels

Molecular reactions Electrocyclic

Molecular reactions Sigmatropic

Molecular reactions states

Molecular reactions transition

Molecular rearrangement metathesis reactions

Molecular rearrangement oxidation reactions

Molecular rearrangement reactions

Molecular rearrangement reactions, thermal degradation

Molecular rearrangement thermal reactions

Molecular rearrangements Grignard reactions

Molecular rearrangements Wittig reaction

Molecular rearrangements aromatic reactions

Molecular rearrangements carbene reactions

Molecular rearrangements ylide reactions

Molecular rearrangements zwitterion reactions

Molecular species, reactions between

Molecular structure kinetic reactions

Molecular surface scattering reaction dynamics

Molecular symmetry group, reaction paths

Molecular systems catalytic reaction networks

Molecular systems reaction environments

Molecular systems reaction rates

Molecular systems very high pressure chemical reactions

Molecular weight amination reactions, polymer synthesis

Molecular weight distributions reaction time

Molecular wire compounds reactions

Molecular-orbital calculations Diels-Alder reactions

Molecular-orbital calculations addition reactions

Molecular-orbital calculations electrocyclic reactions

Molecular-orbital calculations elimination reactions

Molecular-orbital calculations pericyclic reactions

Molecular-orbital calculations reactions

Molecularity of a reaction

Molecularity of an Elementary Reaction

Molecularity of reaction

Molecularity reaction order and

Molecularity reactions and

Molecularity substitution reactions

Molecularity, of elementary reactions

Multi-electron mechanisms of redox reactions Switching molecular devices

Orbitals, molecular reactions

Order of reaction molecularity and

Organic Name Reactions Useful in Biochemistry and Molecular Biology

Ozone reaction with singlet molecular oxygen

Ozone reactions producing singlet molecular

Pericyclic reactions frontier molecular orbital theory

Pericyclic reactions highest occupied molecular orbital

Pericyclic reactions lowest unoccupied molecular orbital

Pericyclic reactions molecular orbital theory

Pericyclic reactions molecular orbitals

Phase-inverting reactions molecular model

Photo-reaction molecular model

Photoinduced reactions, molecular

Photoinduced reactions, molecular chemical methods

Photoinduced reactions, molecular oxygen

Photoinduced reactions, molecular yield

Polyatomic molecular reactions, with

Polyatomic reactions, molecular potential

Polyatomic reactions, molecular potential energy

Potential Energy Surface Molecular Structure, Transition States, and Reaction Paths

Precipitation Reactions Total Molecular Equations

QUALITATIVE MOLECULAR ORBITAL THEORY AND PERICYCLIC REACTIONS

Qualitative molecular orbital theory of reactions

Radical transfer reactions to low molecular mass species

Rate orders and Molecularity of a reaction

Reaction Pathways for the Reduction of Molecular Oxygen

Reaction balanced molecular

Reaction between Molecular Hydrogen and Chlorine

Reaction between Molecular Hydrogen and Iodine

Reaction control molecular cages

Reaction mechanism molecularity

Reaction mechanisms and molecularity

Reaction mechanisms experimental molecular study

Reaction mechanisms molecular beam reactions

Reaction mechanisms molecular dynamics principles

Reaction molecular theory

Reaction of Polymer-Heme Complexes with Molecular Oxygen

Reaction order molecularity

Reaction pathways molecular labeling

Reaction products molecular weights

Reaction rate molecular structure and

Reaction rates molecular mechanism

Reaction with Low Molecular Weight Alcohols - the Fischer Glycoside Synthesis

Reactions describing molecularity

Reactions molecular clusters

Reactions molecular oxygen

Reactions molecularity

Reactions of Carbosilanes Containing Side Chains Bonded to Si-Atoms in the Molecular Skeleton

Reactions of Functionalized TSOSs in Molecular Solvents

Reactions of NHC-coordinated Metal Complexes with Molecular Oxygen

Reactions of free radicals with molecular oxygen

Reactions of molecular oxygen with nitrogen compounds

Reactions qualitative molecular orbital theory

Reactions with Molecular Oxygen

Reactions, Information, and Molecular Structure

Ring-opening reactions inducing molecular rearrangements

Role of Water in Radical Reactions Molecular Simulation and Modelling

Sharpless reaction molecular sieves

Silylene reaction with molecular oxygen

Simple radical reactions, molecular

Singlet Molecular Oxygen Reaction

Singlet molecular oxygen reactions with

Solid-state reactions molecular attachment

Specific Molecular Reactions

Synthesis of Low Molecular Weight Compounds through Fast Reactions in Turbulent Flows

Synthesis reactions molecular scale

The Representation of Molecular Species and Reactions between Them

The molecular beam method basic concepts and examples of bimolecular reaction studies

Titanium silicate molecular sieves oxidation reactions

Triflate catalysts, molecular metal reactions

Velocity distribution 592 molecular reaction

What is molecular reaction dynamics

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