Rational scaling rate constant

The rational rate constant is defined as the rate of growth over unit area, in equivalents per second, of a scale of unit thickness, i.e., Equation (3.98),... 

The kinetics of formation and/or dissociation of the mono-complex of Ni with isoquinoline have been measured in a variety of solvents (Table 1). Neither the dissociation rate constant nor the overall equilibrium constant for complex formation correlates with Gutmann s donicity scale for solvents, but the activation enthalpy for dissociation does show a linear relationship with solvent donicity. This, conclude the authors, can be rationalized from a mechanistic point of view by assuming that the solvent molecules co-ordinated to the metal ion help to stabilize the transition state. A similar correlation between A/f J donicity (Table 1) is found ... 

Quantitative relationships have been reported between the global electrophilicity index and the experimental rate coefficients for the reactions of thiolcarbonates and dithio-carbonates with piperidine. The validated scale of electrophilicity was then used to rationalize the reaction mechanisms of these systems. This scale also makes it possible to predict both rate coefficients and Hammett substituent constants for a series of systems that have not been experimentally evaluated to date.48... 

The use of eq. (12-30), a breakage equation, to correlate data for coalescing systems can be further rationalized by reference to eq. (12-35). Since the b cj) term represents the coalescence frequency, the use of eq. (12-30) suggests that there is a constant coalescence efficiency represented by b and a constant collision rate that is proportional to 4). Presently, there is no systematic way to relate b to the many factors governing coalescence, and there is no way to extend the approach to viscous drops. This empirical approach, although simple to use, lacks technical interpretation and is therefore risky to apply for scale-up work. 

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