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Chemistry

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  • $\begingroup$ I'm afraid I still don't follow. In your last equation, what is w, and why is it the negtative of the optical density? Additionally, doesn't it still imply that the extinction coefficient at a given wavelength is still inversely proportional to the concentration of the species? Working through the maths I get the relation: (e(water, measured) - e0) / e0, where e0 is the extinction coefficient for the initial concentration and e(water, measured) is equilivent to eW in my post. $\endgroup$
    – K.P.
    Commented Nov 19, 2018 at 11:54
  • $\begingroup$ The equation you quote has $\epsilon^{+w}$ and from Beers law it should be $e^{-\epsilon [C]L}$ so $-w$, it may be my misunderstanding from what you wrote I has assume that it was a typo and $\epsilon^{w}$ should actually be $e^w$. $\endgroup$
    – porphyrin
    Commented Nov 19, 2018 at 12:08
  • $\begingroup$ Ah that’s my fault - I didn’t define the terms in my equation because they were defined in the link. I’ve now edited it to make it more clear - the terms in the equation are all extinction coefficients; the W superscript says that they are the extinction coefficients in water solvent. This means when I wrote e in my first reply to you I meant epsilon, the extinction coefficients. $\endgroup$
    – K.P.
    Commented Nov 19, 2018 at 13:34
  • $\begingroup$ I realized that in my calculations I erroneously cancelled Ao and A with each other. Now working through the mathematics I can't seem to get the desired equation at all. $\endgroup$
    – K.P.
    Commented Nov 19, 2018 at 16:38