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### Topic: Calculation of %Absorbance  (Read 3980 times)

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#### serotonin

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##### Calculation of %Absorbance
« on: May 12, 2024, 07:41:04 AM »
hey can someone please correct me if I'm wrong (it's for an exam I have tomorrow)

The molecule ΑΧ2Ε2 shows an absorbance of 1.00 at a wavelength of 5 µm. What is the % percentage of the incident radiation (Io) that is absorbed?

I did: A=log(Io/I) => 10=Io/I => %A=(I/Io)*100=> I/Io=1/10 => 1/10*100=10%
I didn't use the wavelength that is why I'm asking! Thank you for any hlp!
« Last Edit: May 12, 2024, 09:33:02 AM by serotonin »

#### Corribus

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##### Re: Calculation of %Absorbance
« Reply #1 on: May 12, 2024, 11:25:42 AM »
You are correct, you do not need the wavelength to solve this problem.
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

#### serotonin

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##### Re: Calculation of %Absorbance
« Reply #2 on: May 12, 2024, 11:28:45 AM »
THANK YOU SO MUCH FOR REPLYING!!

#### mjc123

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##### Re: Calculation of %Absorbance
« Reply #3 on: May 12, 2024, 03:15:21 PM »
You have calculated the % transmitted, not absorbed.

#### NotSoSure

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##### Re: Calculation of %Absorbance
« Reply #4 on: May 13, 2024, 07:13:45 AM »
Thank you for your reply... Is there any chance you help me with the equation I need..My exam is in 2 hours :'/ thanks again . Or should I 100-10?

#### Corribus

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##### Re: Calculation of %Absorbance
« Reply #5 on: May 13, 2024, 09:40:45 AM »
If the percent transmitted is X, then the percent absorbed is 100-X (with certain assumptions).
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

#### serotonin

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##### Re: Calculation of %Absorbance
« Reply #6 on: May 13, 2024, 04:50:43 PM »
thanks very much!