Enter the molar absorption coefficient, concentration, and path length into the calculator to determine the total absorbance.
Beer-Lambert Law Formula
The following equation is used to calculate the absorbance of a substance.
A = ma * c * l
- Where A is the absorbance
- ma is the molar absorption coefficient (m*2/mol)
- c is the concentration (mol/L)
- l is the path length (m)
Beer-Lambert Law Definition
The Beer-Lambert law defines the phenomena that the absorbance of a substance is proportional to the product of the concentration and length.
Beer-Lambert Law Example
How to calculate absorption from the Beer-Lambert law?
- First, determine the coefficient.
Calculate the molar absorption coefficient of the substance.
- Next, determine the concentration.
Calculate the concentration of the substance.
- Next, determine the path length.
Calculate the length of the path in which the substance can be absorbed.
- Finally, calculate the absorption.
Calculate the absorption using the formula above.
FAQ
This law states that the absorbance is proportional to the length and the concentration of a material.

