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Coefficients in reactions

To keep the units straight, we need to use the molar convention for this calculation and to use the stoichiometric coefficients in reaction E as pure numbers. To find an expression for AGr, we substitute F q. 4 for each substance into Eq. 3a. For example, for the general reaction E,... [Pg.485]

Brown, K. J. and Eilbeck, J. C. (1982). Bifurcation, stability diagrams and varying diffusion coefficient in reaction-diffusion equations. Bull. Math. Biol., 44, 87-102. [Pg.262]

The family of methods for the study of parametric information in mathematical models is called sensitivity analysis. Sensitivity analysis investigates the relationship between the parameters and the output of any model. It is usually used for two purposes first, for uncertainty analysis and, second, for gaining insight into the model. Sensitivity methods in chemical kinetics have been reviewed by Rabitz et al. [64], who concentrated mainly on the interpretation of sensitivity coefficients in reaction-diffusion systems. Turdnyi [12] considered sensitivity methods as tools for studying reaction kinetics problems and reviewed several applications. Recently, Radha-... [Pg.315]

Note that the coefficients in reaction (3.67) conld jnst as easily have been all divided by two to scale the stoichiometry to the exchange of a single electron (as is done in Table 3.7), withont cansing any change in the calculated Ej, value. The Ej, of water varies non-linearly with the concentration of oxygen and is not very sensitive to the O2 concentration. For example, a 99% decrease in [O2] causes only a 4% drop in the Ej, of the water. (Saturated water, 0.2 atm, has an E of 0.75 V water with only 1% O2 saturation, 0.002 atm, has an E of 0.72 V.) Thus, as long as measurable amounts of dissolved O2 remain, the E of seawater will continue to be very positive. [Pg.93]

It is improbable that the value of the preexponential coefficient would exceed the frequency factor by one or two orders of magnitude. Possibly the reason for the abnormally high steric coefficient in Reaction 1 is its deviation from the Polyani-Semenov rule, although the activation energy calculated by Moin (15) gives the same result within the limits of the precision of this method. In any case, the low limit of the activation energy of the Voevodsky reaction is its thermal effect. Accepting the fact that Reactions 3 and 8 proceed without an activation barrier, P3 = 0.2 and P2 0.03. [Pg.120]

Despite practical difficulties, tritium tracers can be used to dissect the various isotope effects which are incorporated in the direct rate comparisons for substrates having secondary or primary beta carbon. The requisite rate coefficients in reaction (66) can be calculated from a knowledge of the mole fraction reacted (/), the molar activity of the reactant (M,) and the product Mi) at that time, and the initial molar activity (Mo) of the reactant (67, 68) - ... [Pg.194]

Chemical reactions change only forms of existence of basis components in compliance with conditions of mass conservation law. Proportions, which equate moles of the components before and after reactions, are called stoichiometric coefficients or simply reaction coefficients. In reaction equations these coefficients are inserted before formulae of the compounds themselves. For instance, the silicon, when solved in water, forms orthosilicic acid, which with increase in pH loses oxygen. For this reason the entire reaction of dissolving SiO may be expressed by the equation... [Pg.50]

As before, the coefficients in reaction (2.9) will be determined by stoichiometry, the amount of energy needed, and the restrictions on the effluent. For example, is it acceptable to have carbon dioxide in the product How about water Methane is less expensive than electricity, but there is yet a cheaper source of energy - coal. We designate coal by its chief constituents as CxHy, where typically x lOy, and the (unbalanced) reaction is... [Pg.26]

We have enormous flexibility in writing the balanced stoichiometric equation for a chemical reaction. This flexibility may create ambiguity in writing the equilibrium expression. Suppose that the stoichiometric coefficients in Reaction (1-1) aU are multiplied by some number, say N. Let s carry out this operation ... [Pg.26]


See other pages where Coefficients in reactions is mentioned: [Pg.152]    [Pg.79]    [Pg.579]    [Pg.23]    [Pg.145]    [Pg.96]    [Pg.432]    [Pg.23]    [Pg.584]    [Pg.24]    [Pg.161]    [Pg.643]    [Pg.79]    [Pg.193]    [Pg.138]    [Pg.11]    [Pg.11]    [Pg.11]    [Pg.11]    [Pg.202]   
See also in sourсe #XX -- [ Pg.284 , Pg.285 , Pg.288 ]




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Reaction coefficients

Reactions and reaction rate coefficients for the formation of water in star forming regions

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