GreenD
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Trouble with excel graph, need help!
That value for your slope is not epsilon, I don't know why you think that.
Beer's law is A=ebc
e = epsilon [Liters / (mol • cm)]
b = path length
c = concentration
Your slope is Absorbance / concentration.
You still need b to calculate epsilon.
e= Abosrbance / (Concentration * cm)
What is the path length?
[Edited on 13-2-2012 by GreenD]
[Edited on 13-2-2012 by GreenD]
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GreenD
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I just did the plot myself and got a slop of 3.1
not sure what you did there.
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GreenD
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I figured it out. Look at the spacings on your x-axis.
they go; 4, 8, 12, etc - not sure how you accomplished that, but your slope is logarithmic or exponential. . .
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White Yeti
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Quote: Originally posted by GreenD  | That value for your slope is not epsilon, I don't know why you think that.
Beer's law is A=ebc
e = epsilon [Liters / (mol • cm)]
b = path length
c = concentration
Your slope is Absorbance / concentration.
You still need b to calculate epsilon.
e= Abosrbance / (Concentration * cm)
What is the path length? |
I know, but since the path length remains constant throughout the whole experiment, its value is trivial. I will find epsilon by dividing the slope of
the graph by the path length, but to find the concentration, I will have to multiply epsilon by the path length, leading back to where I started.
I will check my x axis markings once again and will reply the problem is solved.
"Ja, Kalzium, das ist alles!" -Otto Loewi
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White Yeti
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Problem solved. I chose the wrong scatterplot option -.-
Thanks for the help. I'll delete the useless thread now.
"Ja, Kalzium, das ist alles!" -Otto Loewi
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