Sciencemadness Discussion Board

Law of mass action?

Wolfram - 4-2-2007 at 09:45

Sorry it was some years ago that I worked with fundamental chemisty could you help me?

I have the follwing equation:

d[AR]/dt=k1([A]-[AR])([R]-[AR])-k2([AR])

It describes the change in concentration of a receptor (R) a agonsist a and a
receptor-agonist complex (AR). But how is it with the formal calculations?
If the expression k1([A]-[AR])([R]-[AR]) should result in a M^2 unit
how could this be substracted from k2([AR]) which is a M^1 unit?

Have I missed something?

Thank you for any help

Magpie - 4-2-2007 at 19:04

It has been some time for me also but I believe that any disparity in the units is provided for by the different units of the rate constants k1 and k2.

Ozone - 4-2-2007 at 20:58

It should all work out to mol/s-1. In your derivation there should be a Mo (starting moles) and an M (moles at some differential time, t.

I'll give this some more attention (I have worked this out in the last year or so) tomorrow when I have had some rest (I have it on paper, but am too tired to transcribe (or manually derive) it here).

Good night,

O3