The Beer-Lambert law (sometimes also known as the Beer-Lambert-Bouguer law or simply Beer's law) is used in
spectroscopy. The
law can be summed up by the
mathematic relationship Aλ=ECL, where A is the
absorbance at a given
wavelength of
light, E is the
molar extinction coefficient, C is the
concentration of the
molar
solution, and L is the
length of the
light path.
In words, the equation means that the concentration of a substance in moles is proportional to the absorption of a given wavelength of light by a solution of the substance.
From the BioTech Dictionary at http://biotech.icmb.utexas.edu/. For further information see the BioTech homenode.