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Meaning of colorimeter values?

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So i am working on a lab report related to the use of a colorimeter. So from research it is said that the values are the most accurate from 0-1, acceptable from 2 to below 3. I wonder what does this value mean? E.g. i got 0.9156 for blue absorption. What does it mean then? 

Thanks! 

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For the Beer-Lambert's law, it means the your absorbance should be between 0 and 1. For example I once used too concentrated potassium permanganate and the data was completely skewed.
%T = 10
-A+2, which relates %transmittance and absorbance. It's similar to [H+] and pH, except for a adjusting factor of 100% or 102%. 0.9156 is roughly 12% of incident light makes through the solution. Higher absorbance means less light is transmitted. Although absorbance is not expressed as a percentage and you can't say the 1.000 absorbance solution absorbs twice as much light as 0.500, you can use the Beer-Lambert law to find concentration of the solution. http://www.epolin.com/converting-absorbance-transmittance
Beer-Lambert's Law: http://life.nthu.edu.tw/~labcjw/BioPhyChem/Spectroscopy/beerslaw.htm

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Thanks so much! Finally figured it out!

I would also like to know is it wise to put values greater than 2 into my lab report? Like can i say they are unreliable but can still be taken as reference? Since my product formed too quickly lol 

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Yeah that's fine. Next time you should dilute the the solution until you can see through the solution (transparent). So if you diluted it to 10 times volume then you have to remember to multiply concentration back by 10 times when you use Beer's Law.

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