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Rate equation. In chemistry, the rate equation (also known as the rate law or empirical differential rate equation) is an empirical differential mathematical expression for the reaction rate of a given reaction in terms of concentrations of chemical species and constant parameters (normally rate coefficients and partial orders of reaction) only ...
In chemical kinetics, a reaction rate constant or reaction rate coefficient ( ) is a proportionality constant which quantifies the rate and direction of a chemical reaction by relating it with the concentration of reactants. [1] For a reaction between reactants A and B to form a product C, a A + b B → c C. where.
So, when a reaction has a rate constant that obeys the Arrhenius equation, a plot of ln k versus T −1 gives a straight line, whose gradient and intercept can be used to determine E a and A. This procedure has become so common in experimental chemical kinetics that practitioners have taken to using it to define the activation energy for a ...
The steady state approximation, [1] occasionally called the stationary-state approximation or Bodenstein's quasi-steady state approximation, involves setting the rate of change of a reaction intermediate in a reaction mechanism equal to zero so that the kinetic equations can be simplified by setting the rate of formation of the intermediate equal to the rate of its destruction.
Rate-determining step. In chemical kinetics, the overall rate of a reaction is often approximately determined by the slowest step, known as the rate-determining step (RDS or RD-step[1] or r/d step[2][3]) or rate-limiting step. For a given reaction mechanism, the prediction of the corresponding rate equation (for comparison with the experimental ...
Plateau principle. The plateau principle is a mathematical model or scientific law originally developed to explain the time course of drug action (pharmacokinetics). [1] The principle has wide applicability in pharmacology, physiology, nutrition, biochemistry, and system dynamics. It applies whenever a drug or nutrient is infused or ingested at ...
In biochemistry, Michaelis–Menten kinetics, named after Leonor Michaelis and Maud Menten, is the simplest case of enzyme kinetics, applied to enzyme-catalysed reactions of one substrate and one product. It takes the form of a differential equation describing the reaction rate (rate of formation of product P, with concentration ) to , the ...
Using the Eyring equation, there is a straightforward relationship between ΔG ‡, first-order rate constants, and reaction half-life at a given temperature. At 298 K, a reaction with ΔG ‡ = 23 kcal/mol has a rate constant of k ≈ 8.4 × 10 −5 s −1 and a half life of t 1/2 ≈ 2.3 hours, figures that are often rounded to k ~ 10 −4 s ...