What is the formula for calculating rate constant?
If you were wondering how to determine the rate constant for reversible reactions, here’s an easy equation that works for the majority of the cases: K = k₁ / k₋₁ , where K = equilibrium constant of the reaction, k₁ & k₋₁ = rate constants of the forward and backward reactions, respectively.
How do you calculate the rate controlled diffusion constant?
The diffusion-controlled rate constant for a bimolecular reaction between species A and B in solution (expressed in dm3mol-1s-1) can be written as kD = 4000πrABDABNAf(U) where rAB is the encounter distance (expressed in m), DAB = DA + DB is the relative diffusion coefficient (in m2s-1) and f(U) is some function of the …
What is the unit of rate of reaction?
Reaction rates are usually expressed as the concentration of reactant consumed or the concentration of product formed per unit time. The units are thus moles per liter per unit time, written as M/s, M/min, or M/h.
What is the value of the rate constant?
The value of the rate constant is temperature dependent. A large value of the rate constant means that the reaction is relatively fast, while a small value of the rate constant means that the reaction is relatively slow.
What is the specific rate constant?
The rate constant, or the specific rate constant, is the proportionality constant in the equation that expresses the relationship between the rate of a chemical reaction and the concentrations of the reacting substances.
What is the diffusion limited rate constant?
Mechanism. Kinetically perfect enzymes have a specificity constant, kcat/Km, on the order of 108 to 109 M−1 s−1. The rate of the enzyme-catalysed reaction is limited by diffusion and so the enzyme ‘processes’ the substrate well before it encounters another molecule.
What is the formula of rate of diffusion?
Let at constant temperature and pressure, the rate of diffusion or effusion of the gas molecules = r and density = d. According to Graham’s law, r = k/√d, where k is a gas constant.
How do you calculate diffusion speed?
The diffusion coefficient determines the time it takes a solute to diffuse a given distance in a medium. D has the units of area/time (typically cm2/s)….JavaScript is not enabled in your browser.
| Ion/Molecule | Atomic/Molecular Weight (g/mol) | Diffusion Coefficient (cm2/s) |
|---|---|---|
| H+ | 1.008 | 9.31 × 10-5 |
| Na+ | 22.990 | 1.33 × 10-5 |