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Extinction Coefficient & Molar Extinction Coefficient

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One knows that the Beer-Lambert law, expresses the relationship of the spectrophotometric absorbance (Abs) of a solution of a compound to the concentration(c) and light path length (l) of the sample. The proportionality constant, when the solution concentration is in M, is called the molar extinction coefficient (E). One would like to determine the molar extinction coefficient (E) of a "newly discovered compound". One places 3.00 mL of a solution that is 5.37 x 10^-6 M in a 1 cm^2 cuvette. The absorbance that one measures is .863. What is the extinction coefficient? And just to be sure what are the units of the molar extinction coefficient (E)?

Abs=(E)(c)(l)

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Solution Summary

This solution determines the molar extinction coefficient, extinction coefficient and the appropriate units for the coefficient using the Beer-Lambert Law. All steps are shown with brief explanations.

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