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Topic: Finding Absorbance  (Read 1115 times)

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Offline Ed88

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Finding Absorbance
« on: July 17, 2019, 07:24:08 PM »
I am having trouble finding absorbance. I know how to calculate it using beers' law when i have a wavelength. I am given a table of potential mV vs Time. I was told to use -log( I/Io) intensity / average in intensity. I don't know how to calculate that from the data given. I tried finding the average of mV then and using that as Io but when I plug it in origin, the data is incorrect. I was given an example on how to it should look. I tried all different kind of ways to solve for Intensity but still can figure out. Thanks in advance.

Offline Corribus

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Re: Finding Absorbance
« Reply #1 on: July 17, 2019, 08:32:25 PM »
Io is the intensity of the light source without any absorbing species in the beam path. I is the intensity of the light source when the absorbing species are in the beam path. Io should always be greater than I (because absorbance reduces the light intensity.) You haven't provided a whole lot of detail about what you're doing, but if I'm reading between the lines correctly, Io should be your initial voltage measured before you've done any chemistry.
What men are poets who can speak of Jupiter if he were like a man, but if he is an immense spinning sphere of methane and ammonia must be silent?  - Richard P. Feynman

Offline Ed88

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Re: Finding Absorbance
« Reply #2 on: July 17, 2019, 11:40:03 PM »
Thanks for responding, I figured out what I did wrong. The experiment is flash photolysis and I was suppose to take the average from the lowest potential voltage until it reach to normal and use that as my initial intensity for the other trials. I was panicking because my lab is due tomorrow and there is really no one around to ask for help because it's the summer session. That's why I didn't explain myself very clearly.

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