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Mass action, and

Applying the Law of Mass Action and taking the activity of un-ionised water as unity, we have ... [Pg.45]

In these equations the independent variable x is the distance normal to the disk surface. The dependent variables are the velocities, the temperature T, and the species mass fractions Tit. The axial velocity is u, and the radial and circumferential velocities are scaled by the radius as F = vjr and W = wjr. The viscosity and thermal conductivity are given by /x and A. The chemical production rate cOjt is presumed to result from a system of elementary chemical reactions that proceed according to the law of mass action, and Kg is the number of gas-phase species. Equation (10) is not solved for the carrier gas mass fraction, which is determined by ensuring that the mass fractions sum to one. An Arrhenius rate expression is presumed for each of the elementary reaction steps. [Pg.342]

The rate of an exothermic chemical reaction determines the rate of energy release, so factors which affect reaction kinetics are important in relation to possible reaction hazards. The effects of proportions and concentrations of reactants upon reaction rate are governed by the Law of Mass Action, and there are many examples where changes in proportion and/or concentration of reagents have transformed an... [Pg.2123]

Fortunately, few of these variables are truly independent. Geochemists have developed a variety of numerical schemes to solve for equilibrium in multicomponent systems, each of which features a reduction in the number of independent variables carried through the calculation. The schemes are alike in that each solves sets of mass action and mass balance equations. They vary, however, in their choices of thermodynamic components and independent variables, and how effectively the number of independent variables has been reduced. [Pg.30]

Most analyses of kinetic data have the object of identifying the constants of a rate equation based on the law of mass action and possibly some mass transfer relation.. The law of mass action Is expressed In terms of concentrations of the participants, so ultimately the chemical composition must be known as a function of time. In the laboratory the chemical composition Is determined by some instrument that is suitably calibrated to provide the needed information. Titration, refractive index, density, chromatography, spectrometry, polarimetry, conductimetry, absorbance, magnetic resonance — all of these are used at one time or another to measure chemical composition. In some cases, the calibration to chemical composition is linear with the reading. [Pg.105]

For adsorption at the IHP, mass action and material balance equations could be set up for specifically adsorbed ions yielding equations similar to those for the surface plane... [Pg.66]

In this connection, Servos mentions, among others, Robert Bunsen at Heidelberg, who invented the carbon-zinc battery and the spectroscope H. H. Landolt at Bonn, later Berlin, who studied the refractive power of the molecule in relation to the refractivities of its atoms Heinrich Rose at Berlin, who followed up on Berthollet s theory of mass action and Cato Guldberg and Peter Waage in Norway, who did so more thoroughly. See John W. Servos, Physical Chemistry from Ostwald to Pauling, 1115. [Pg.124]

The underlying principles and theories of gravimetric analysis are as stated below (/) Law of mass action and reversible reactions,... [Pg.173]

How does the Law of Mass Action and Reversible Reactions help in accomplishing the gravimetric analysis Explain. [Pg.189]

As expected, the trace in Figure 5-19 is less ordered than the equivalent in Figure 5-18. Concentration profiles are governed by the law of mass action and closure and thus the trace, following the rows of US, is structured accordingly. No such law governs the relative shape of the absorption spectra and the trace following the columns of SV. [Pg.239]

Two additional points about Equation (8) need to be discussed here. Equation (8) contains mj in the denominator. Thus the solution concentrations must be known before the first increment dE, is taken and none of them can be zero. In practice this means that the set of nonlinear equations (mass action and balance equations) describing the fluid phase in its initial unperturbed equilibrium state must be solved once. Further, Equation (8) does not completely describe a heterogeneous system at partial equilibrium. [Pg.744]

Applications of chemical kinetics to enzyme-catalyzed reactions soon followed. Because of the ease with which its progress could be monitored polarimetrically, enzyme hydrolysis of sucrose by invertase was a popular system for study. O Sullivan and Tompson (1890) concluded that the reaction obeyed the Law of Mass Action and in a paper entitled, Invertase A Contribution to the History of an Enzyme or Unorganized Ferment , they wrote [Enzymes] possess a life function without life. Is there anything [in their actions] which can be distinguished from ordinary chemical action ... [Pg.181]

In the absence of an enzyme, the reaction rate v is proportional to the concentration of substance A (top). The constant k is the rate constant of the uncatalyzed reaction. Like all catalysts, the enzyme E (total concentration [E]t) creates a new reaction pathway, initially, A is bound to E (partial reaction 1, left), if this reaction is in chemical equilibrium, then with the help of the law of mass action—and taking into account the fact that [E]t = [E] + [EA]—one can express the concentration [EA] of the enzyme-substrate complex as a function of [A] (left). The Michaelis constant lknow that kcat > k—in other words, enzyme-bound substrate reacts to B much faster than A alone (partial reaction 2, right), kcat. the enzyme s turnover number, corresponds to the number of substrate molecules converted by one enzyme molecule per second. Like the conversion A B, the formation of B from EA is a first-order reaction—i. e., V = k [EA] applies. When this equation is combined with the expression already derived for EA, the result is the Michaelis-Menten equation. [Pg.92]

For an unknown reaction, the reaction law cannot be written down simply by looking at the reaction equation. Instead, experimental study must be carried out on how the reaction rate depends on the concentration of each species. For elementary reactions, the reaction rate follows the law of mass action and can be written by looking at the reaction. If the following reaction is an elementary reaction... [Pg.15]

In this section we consider the thermodynamics of micellization from two points of view the law of mass action and phase equilibrium. This will reveal the equivalency of the two approaches and the conditions under which this equivalence applies. In addition, we define the thermodynamic standard state, which must be understood if derived parameters are to be meaningful. [Pg.370]

In pure FeO, the point defects are primarily Schottky defects that satisfy mass-action and equilibrium relationships similar to those given in Eqs. 8.39 and 8.42. When FeO is oxidized through the reaction... [Pg.181]

The kinetics of combustion reactions turn out to be quite complicated they do not satisfy the classical law of mass action and its kinetic formulation. Neither did Duhem s formal conceptions of the existence of regions of false equilibria and of a special chemical friction, which ignores the molecular mechanism of chemical reactions, correspond to reality. [Pg.163]

Several models have been developed to interpret micellar behavior (Mukerjee, 1967 Lieberman et al., 1996). Two models, the mass-action and phase-separation models are described here in mor detail. In the mass-action model, micelles are in equilibrium with the unassociated surfactant or monomer. For nonionic surfactants with an aggregation numb itbfe mass-action model predicts thatn molecules of monomeric nonionized surfactaStajeact to form a micelleM ... [Pg.263]


See other pages where Mass action, and is mentioned: [Pg.25]    [Pg.326]    [Pg.10]    [Pg.276]    [Pg.249]    [Pg.52]    [Pg.158]    [Pg.59]    [Pg.62]    [Pg.174]    [Pg.546]    [Pg.742]    [Pg.220]    [Pg.48]    [Pg.58]    [Pg.111]    [Pg.293]    [Pg.384]    [Pg.494]    [Pg.25]    [Pg.71]    [Pg.613]    [Pg.490]   
See also in sourсe #XX -- [ Pg.35 , Pg.36 , Pg.37 , Pg.38 , Pg.39 ]




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