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Theory of reactions

The existence of the polyad number as a bottleneck to energy flow on short time scales is potentially important for efforts to control molecnlar reactivity rising advanced laser techniqnes, discussed below in section Al.2.20. Efforts at control seek to intervene in the molecnlar dynamics to prevent the effects of widespread vibrational energy flow, the presence of which is one of the key assumptions of Rice-Ramsperger-Kassel-Marcns (RRKM) and other theories of reaction dynamics [6]. [Pg.75]

Specific solute-solvent interactions involving the first solvation shell only can be treated in detail by discrete solvent models. The various approaches like point charge models, siipennoleciilar calculations, quantum theories of reactions in solution, and their implementations in Monte Carlo methods and molecular dynamics simulations like the Car-Parrinello method are discussed elsewhere in this encyclopedia. Here only some points will be briefly mentioned that seem of relevance for later sections. [Pg.839]

Hynes J T 1985 The theory of reactions in solution Theory of Chemical Reaction Dynamics ed M Baer (Boca Raton, FL CRC Press) pp 171-234... [Pg.869]

Much of the basic theory of reaction kinetics presented in Sec. 7 of this Handbook deals with homogeneous reaclions in batch and continuous equipment, and that material will not be repeated here. Material and energy balances and sizing procedures are developed for batch operations in ideal stirred tanks—during startup, continuation, and shutdown—and for continuous operation in ideal stirred tank batteries and plug flow tubulars and towers. [Pg.2098]

Neither the principles of thermodynamics nor theories of reaction rates require that there should be such linear relationships. There are, in fact, numerous reaction series that fail to show such correlations. Some insight into the origin of die correlation can be gained by considering the relationship between the correlation equation and the free-energy changes involved in the two processes. The line in Fig 4.2 defines an equation in which m is the slope of the line ... [Pg.205]

Henry Eyring is one of llie most active and honored chemists of our time. His advancement of the theory of reaction rates benefits practically every field of chemistry and chemical technology. His 300 published papers and five books range through chemistry, physics, metallurgy, and biology. [Pg.141]

From a practical point of view, it would be very desirable to have reliable rules, even if only empirical, which could provide estimates of barrier heights in the absence of experimental data. This would be of obvious use in predicting thermodynamic quantities for stable molecules and would also be most valuable in testing and applying theories of reaction rates. Furthermore, any empirical regularities observed could be helpful in the development of a theoretical treatment of barriers. [Pg.381]

FIGURE 13.30 A reaction profile for an exothermic reaction. In the activated complex theory of reaction rates, it is supposed that the potential energy (the energy due to position) increases as the reactant molecules approach each other and reaches a maximum as they form an activated complex. It then decreases as the atoms rearrange into the bonding pattern characteristic of the products and these products separate. Only molecules with enough energy can cross the activation barrier and react to form products. [Pg.684]

The reason for this varied behaviour is not difficult to find. A population of bacteria does not possess the uniformity of properties inherent in pure chemical substances. This fact, together with the varied manner in which bactericides exert their effect and the complex nature of the bacterial cell, should provide adequate and satisfying reasons why the precise theories of reaction kinetics should have failed to explain the disinfeclion process. [Pg.232]

Why does the collision theory of reaction rates conflict with equilibrium... [Pg.404]

J. C. Keck, Variational theory of reaction rates, Adv. Chem. Phys. 13, 85 (1967). [Pg.234]

About three years after Wachtershauser s first publication appeared, an article by Christian de Duve and Stanley Miller was published in the Proceedings of the National Academy of Sciences under the title Two-Dimensional Life the title alluded to the theory of reactions at positively charged pyrite surfaces (de Duve and Miller, 1991). Their criticisms of the chemoautotrophic theory were directed particularly towards certain kinetic and thermodynamic aspects, but also to theoretical statements for which no experimental support was available. [Pg.201]

The collision theory of reaction rates states that molecules, atoms or ions must collide effectively in order to react. For an effective collision to occur, the reacting species must have (1) at least a minimum amount of energy in order to break old bonds and make new ones, and (2) the proper orientation toward each other. [Pg.259]

Irreversible statistical mechanics could in principle be used to develop a fundamental theory of reaction rates by treating chemical reaction as the response to chemical potential fluctuations against a reaction barrier, A. [Pg.492]

Equations 3.1-6 to -8 are all forms of the Arrhenius equation. The usefulness of this equation to represent experimental results for the dependence of kA on Tand the numerical determination of the Arrhenius parameters are explored in Chapter 4. The interpretations of A and EA are considered in Chapter 6 in connection with theories of reaction rates. [Pg.44]

In the preceding chapters, we are primarily concerned with an empirical macroscopic description of reaction rates, as summarized by rate laws. This is without regard for any description of reactions at the molecular or microscopic level. In this chapter and the next, we focus on the fundamental basis of rate laws in terms of theories of reaction rates and reaction mechanisms. ... [Pg.115]

In many cases, reaction rates cannot be adequately represented by equation 6.1-1, but are more complex functions of temperature and composition. Theories of reaction kinetics should also explain the underlying basis for this phenomenon. [Pg.116]

The simple theories of reaction rates involve applying basic physical chemistry knowledge to calculate or estimate the rates of successful molecular encounters. In Section 6.3 we present important results from physical chemistry for this purpose in subsequent sections, we show how they are used to build rate theories, construct rate laws, and estimate the values of rate constants for elementary reactions. [Pg.120]

The collision theory of reaction rates in its simplest form (the simple collision theory or SCT) is one of two theories discussed in this chapter. Collision theories are based on the notion that only when reactants encounter each other, or collide, do they have the chance to react. The reaction rate is therefore based on the following expressions ... [Pg.128]


See other pages where Theory of reactions is mentioned: [Pg.54]    [Pg.782]    [Pg.424]    [Pg.42]    [Pg.438]    [Pg.200]    [Pg.230]    [Pg.88]    [Pg.92]    [Pg.96]    [Pg.679]    [Pg.969]    [Pg.19]    [Pg.422]    [Pg.424]    [Pg.129]    [Pg.76]    [Pg.20]    [Pg.233]    [Pg.46]    [Pg.384]    [Pg.105]    [Pg.105]    [Pg.329]    [Pg.254]    [Pg.42]    [Pg.57]    [Pg.115]    [Pg.128]   
See also in sourсe #XX -- [ Pg.190 ]




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Acceptor-donor (AD) theory of chemical reactions

Adiabatic theory of reactions

Analytic theory of chemical reactions

Application of Marcus Theory to other Protein Electron Transfer Reactions

Application of absolute rate theory to bimolecular surface reactions

Chemical Reactions General Theory of Catalysis

Collision Theory of Unimolecular Reactions

Collision theory and rates of reaction

Collision theory of chemical reaction rates

Collision theory of chemical reactions

Collision theory of gas-phase reactions

Collision theory of gaseous reactions

Collision theory of reaction rates

Collision theory of reactions

Concepts of Elementary Reaction Act Theory

Development of the Conjugated Reaction Theory in Later Works

Diffusion theory of reactions

Electronic theory of photocatalytic reactions on semiconductors

Equilibrium Theory of Reaction Rates The Transition-state Method

Film theory analysis of gas-liquid-solid reactions

Inclusion of a chemical reaction into kinetic theory

Kinetic Theories of Elementary Reactions

MO Theory of Pericyclic Reactions

On the Theory of Non-adiabatic Chemical Reactions

Predictability of Reaction Rate from Theory

Qualitative Theory of Solvent Effects on Reaction Rates

Qualitative molecular orbital theory of reactions

Quantitative Theories of Solvent Effects on Reaction Rates

Quantum theory of electron-transfer reactions

RRKM theory and the rate of unimolecular reactions

Similarity in the Theory of Pericyclic Reactions

Simple Collision Theory (SCT) of Bimolecular Gas-Phase Reactions

Simple Collision Theory of Reaction Rates

Single electrode reaction comparison of experiment and theory

Slater theory, of unimolecular reactions

Statistical theory of bimolecular reactions

Statistical theory of nuclear reactions

Statistical theory of unimolecular reactions

Stochastic theory of bistable reactions

THE THEORY OF PERICYCLIC REACTIONS

Temperature Dependence of Reaction Kinetics Activation Theory

The Activated Complex Theory of Bimolecular Chemical Reaction Rates in Dilute Gases

The Collision Theory of Chemical Reactions

The Hierarchy and Competition of Reaction Theories

The Theory of Unimolecular Reactions

The collision theory of gaseous reactions

The collision theory of reaction rates

The theory of absolute reaction rates

Theories of Organic Reactions

Theories of Unimolecular Reactions

Theories of reaction kinetics

Theory Formulation of Reaction Rates

Theory of Bimolecular Reactions

Theory of Electron Transfer Reactions

Theory of Heterogeneous Electron-Transfer Reactions

Theory of Outer-Sphere Electron Transfer Reactions

Theory of Steady Reaction

Theory of Turing Patterns in the CIMA and CDIMA Reactions Lengyel-Epstein Model

Theory of absolute reaction rates,

Theory of absolution reaction rate

Theory of chemical reactions

Theory of ion-molecule reactions

Theory of solid state reaction kinetics

Thermodynamic and Stochastic Theory of Reaction Diffusion Systems

Transition State Theory in the Treatment of Hydrogen Transfer Reactions

Transition state theory of chemical reactions

Transition state theory of elementary reaction

Transition state theory of gaseous reactions

Transition state theory of reaction rate

Transition state theory of surface reactions

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