I with spectrophotometry ( The Beer-Lambert Law )

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The forum discussion centers on the application of the Beer-Lambert Law in spectrophotometry, specifically in the context of analyzing the antioxidant activity of red wines. The user seeks clarification on the mathematical derivation of the equation %T = e^(-εbc) from the equations A = 2 - log10(%T) and A = εbc. The discussion includes detailed steps for manipulating logarithmic equations and highlights the importance of understanding the relationship between absorbance, transmittance, and molar absorptivity.

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I'm doing a science project about the antioxidant activity of red wines from my country. This days, I was going through the theoretical part ( the basics of spectrophotometry, photometric analysis ect. ) and I'm currently at the Beer-Lambert Law. I'm would like to know the whole mathematical path that is used so that starting from this two equations: A = 2 - log10 %T and A = \epsilonbc,

where:
A is absorbance, ( no units )
T is transmittance, ( no units )
\epsilon is molar absorbtivity, ( L mol-1cm-1 )
b is the length of the sample ( path length of the cuvette ) ( cm ) and
c is the concentration of the compound in solution ( mol L-1 )

the equation %T = e -\epsilonbc is deduced.

note: the molar absorbtivity is represented by the letter epsilon from the Greek alphabet and it's not superscripted as it looks like.

Thanks in advance
 
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Well, let's see...

Start by putting the two equations equal to each other...

2-log_{10}(T)=\epsilon b c

Add log_10(t) to both sides...

2=\epsilon b c + log_{10}(T)

Subtract epsilon b c from both sides...

2- \epsilon b c = log_{10}(T)

And raise both sides to the power of 10.

T=10^2 * 10^{-\epsilon b c}

I got a different answer than that... I'm not sure if that's right.
 
I started just like you ( putting the two equations equal to each other ) but I think that e, from the equation %T = e-\epsilonbc stands for the so called Neper's number ( e = 2,72 ) and after using the rule that:

logab = logcb / logca

and several trasnformations I got stuck here:

loge%T = 2loge10 - \epsilonbc loge10
 

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