Stoichiometric number factor

Transfer Coefficient, Symmetry Factor and Stoichiometric Number... 

Here, Ais the free energy change of Reaction 17.3 (kJ mol 1), R is the gas constant (8.3143 J K-1 mol-1), and 7k is absolute temperature (K). Factor co is the reciprocal of the average stoichiometric number, which can be taken as the number of times the rate determining step in Reaction 17.3 occurs per turnover of the reaction (Jin and Bethke, 2005). 

In this example the exclusion of the intermediates could be effected, essentially in one way only, since the column of stoichiometric numbers ( (2) is obtained from the column (2) by multiplication by an arbitrary factor this holds for any other suitable column of stoichiometric numbers. However, this is not always the case—even when the reaction is described by one overall equation. Thus, a possible mechanism of oxidation of hydrogen on platinum is (25)... 

Stockholm convention 60 stoichiometric number 42 stokes 112 strain 12 bulk 12 linear 12 shear 12 volume 12 stress 12, 72 Strouhal number 65 structural formula 45 structure factor 36 sublimation 51 substance concentration 5 substitution structure distance 24 sum over states 39 surface amount 63 surface charge density 14, 59 surface chemistry 63 surface concentration 42 surface coverage 63 surface density 12 surface electric potential 59 surface excess 63 surface excess concentration 63 surface pressure 63 surface properties 64 surface tension 12, 48, 63 susceptance 15 svedberg 111 symbols 5... 

II.2). In various places in the text, where generality is implied and the process concerned is not necessarily ale, single-step reaction, the transfer coefficient a is written. In the latter case, e.g., when charge transfer is involved in a rate-controlling desorption step, a factor is included in the relevant value of a (see p. 115). t Introduction of the stoichiometric number p, with a and n, in b is sometimes confusing. Some discussion of this matter is to be found in Ref. 13 and in Gileadi s contribution in Chapter 8 of the present author s monograph, Theory and Principles of Electrode Processes, Ref. 25. 

The coupling factor has the subunit structure 03/33766 where a-e denote the type of subunit and the index the corresponding stoichiometrical number. 

Numerical factor (stoichiometric number) indicates relative amount of A consumed see Section 2.4. 

Through version 3245, mass balances in EQ6 were defined by stoichiometric numbers based on elemental composition. In the 3270 version, they will be based upon reaction coefficients. To maintain a maximum degree of correspondence of mass balance totals defined in this manner with physically measurable quantities, the mass balances and associated stoichiometric factors will be defined and maintained in terms of the original (data file) basis set (or more strictly, the reactions written using this set). 

The methods (73,74) which have been widely used to investigate the mechanism of this reaction at several electrodes are determinations of (a) Tafel parameters, (b) stoichiometric numbers, (c) reaction orders, (d) variation of coverage of intermediate (adsorbed hydrogen as the electrode) with potential, and (e) hydrogen-deuterium or hyirogen-tritium separation factors. One of the main difficulties in these mechanism... 

The factor of proportionality is equal to the stoichiometric number oj the ratedetermining step ... 

The term foute was introduced by Horiuti [14-16]. From his point of view, any linear combination of an elementary, linear and non-linear factor with an interface substance s reactions previously multiplied on some stoichiometric numbers satisfying the condition of equality to zero of a stoichiometric coefficient of an intermediate substance represents the route realizing the final chemical transformation. According to Horiuti a stoichiometric number can take any whole-number value in order to satisfy the above-mentioned condition, implying that the number of the runs of the presented elementary reaction via route can be more than 1. 

Results of the experiments have been summarized elsewhere, and only brief comments will be given here (a) results which support the Tafel-Volmer reaction route were obtained on Rh (in acid) and Rh and Ni (in alkaline solution), and partly on Pt, Pd, Ir, Au, and Ag (in acid solutions) (b) elementary step rates are frequently of comparable magnitudes, particularly on Rh and Ni (c) correspondingly, the stoichiometric numbers often deviate from integer values and (d) kinetics of the cathodic component rate of the Tafel step was second order in au, while that of the Volmer step indicated its symmetry factor (1 - /3) to be close to unity. Some results are summarized in Table 1/ ... 

The following biochemical yield factors replace the stoichiometric numbers used in reactions ... 

Qixn consists of a factor for each reactant and product. Each factor is the activity raised to the power of the stoichiometric number Vj. Since the value of v is positive for a product and negative for a reactant, Qrxn is a quotient in which the activities of the products appear in the numerator and those of the reactants appear in the denominator, with each activity raised to a power equal to the corresponding stoichiometric coefficient in the reaction equation. Such a quotient, with quantities raised to these powers, is called a proper quotient. The reaction quotient is a proper quotient of activities. 

Strategy Use the balanced chemical equation to determine the conect stoichiometric conversion factors, and then multiply by the number of moles of ammonia given. 

Strategy Convert each of the reactant masses to moles. Use the balanced equation to write the necessary stoichiometric conversion factor and determine which reactant is limiting. Again, using the balanced equation, write the stoichiometric conversion factors to determine the number of moles of excess reactant remaining and the number of moles of CO2 produced. Finally, use the appropriate molar masses to convert moles of excess reactant and moles of CO2 to grams. 

Now we will discuss using the rate factors fp for step p from left to right and f" from right to left. It is known that the rate factor [SOU 90, p. 247] of an elementary step p is the product of the rate constant k and the concentrations of the reactants and products of total reaction, which intervene as reactants in the Step p and each one raised to the power of their arithmetic stoichiometric number p. A rate factor depends on the temperature via the corresponding rate constant. The factor fp is thus constant if we work at a constant temperature and with constant concentrations of the main reactants and products. 

For the second step, we can build Table 19.8, which gives an equation that must be satisfied for each independent property. We would obviously obtain an equation of less than there are unknown factors because it is known that there is infinity of sets of stoichiometric numbers, all proportional with each other. In our case, the reaction being elementary it utilizes one act which is the meeting of an interstitial oxygen ion with two close OH on the surface, and thus we have a = 2 and b = I, whence the other coefficients are calculated by solving the system of equations of Table 19.8. 

Of course, these schemes indicate only that the overall reactions may be classified as nucleophilic 1,3-substitutions and, in the last case, as electrophilic 1,3-substitut ions. The reactions often proceed only in the presence of catalytic or stoichiometric amounts of transition metal salts, while in their absence 1,1--substitutions or other processes are observed. The 1,1-substitutions are also catalyzed by salts of transition metals, and it is not yet well understood, which factors influence the 1,1 to 1,3-ratio. In a number of 1,3-Substitutions there is... 

Exact numbers, such as the stoichiometric coefficients in a chemical formula or reaction, and unit conversion factors, have an infinite number of significant figures. A mole of CaCb, for example, contains exactly two moles of chloride and one mole of calcium. In the equality... 

The parameter r continues to measure the ratio of the number of A and B groups the factor 2 enters since the monofunctional reagent has the same effect on the degree of polymerization as a difunctional molecule with two B groups and, hence, is doubly effective compared to the latter. With this modification taken into account, Eq. (5.40) enables us to quantitatively evaluate the effect of stoichiometric imbalance or monofunctional reagents, whether these are intentionally introduced to regulate or whether they arise from impurities or side reactions. 

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