Chemical Kinetics Query

AI Thread Summary
The discussion centers on the relationship between the fraction of activated molecules in a chemical kinetics problem and the probability factor in the Arrhenius Equation. The fraction of activated molecules, given as 10^{-15}, is identified as corresponding to the exponential term in the Arrhenius Equation, specifically related to the activation energy and temperature. The frequency factor (A) and probability factor (P) are noted to be influenced by collision rates and molecular geometries, indicating that they are distinct from the fraction of activated molecules. The clarification emphasizes the importance of understanding these components in the context of first-order reactions and their half-lives.
maverick280857
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HI

While working on some chemical kinetics problems, I came across the statement, the fraction of activated molecules is 10^{-15} in a problem where some other constants were also provided and the half life was to be found (for a first order reaction). My specific query is:

Is this fraction equal to the probability factor in the Arrhenius Equation? That is, is this equal to P where

k = APe^{-E_{act}/RT}

where k = rate constant, A = frequency factor, P = probability factor, E_{act} = activation energy and T = absolute temperature?

Or is it something else?

Thanks and cheers
vivek
 
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It'll be better for you if you were to post the exact problem instead of having us guess around (not to sound rude).
 
The fraction of activated molecules is actually the exponential term.

A and P are related to collision rates (T dependent) and molecular geometries (steric effects).
 
Thanks Gokul, you were right about the exponential term.

Cheers
vivek
 
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