equations chem 101l

equations chem 101l - A= bc These variables are defined as...

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A = ε b c These variables are defined as follows: A = absorbance = - log (I/I o ) Where, I = light intensity of sample and I o = light intensity for the blank solution. The colorimeter uses the relative light intensity of the sample together with the light intensity of the blank solution to determine the absorbance value for each sample. Therefore…Absorbance has no units ε = molar extinction coefficient which defines how strongly the solution being studied absorbs light at a particular wavelength. In our case, it is how strongly the FeSCN +2 complex ion absorbs blue light. The molar extinction coefficient is unique for each different chemical at each different wavelength. Typically, molar extinction coefficients are expressed with the units M -1 cm -1 . b = the path length of the light through the solution contained in the cuvette. For most experiments the path length of the cuvette is 1.00 cm. This variable has units of centimeters. c = the concentration in units of
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This note was uploaded on 11/03/2009 for the course BIOL 90726 taught by Professor Weakley during the Spring '09 term at UNC.

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