Molar absorptivity (ε) is a constant that relates the absorbance (A) of a substance to its concentration (c) and the path length (l) of the light beam passing through the sample. It is calculated using the equation: ε = A / (c * l), where A is the absorbance, c is the concentration in moles per liter, and l is the path length in centimeters. The units of molar absorptivity are liters per mole per centimeter (L/(mol*cm)).
