A = abc
A is the absorbance
ÒaÓ is molar absorptivity in L/[(mole)(cm)]
ÒbÓ is the path length in cm
ÒcÓ is the concentration of the analyte
(sample) in mol/L


Beer-Lambert Law (a.k.a. Beer's law) - the linear relationship between absorbance and concentration of an absorbing species.
Absorbance