Concentration is a measure of the amount of a substance in a given volume of solution. It is often expressed in units of moles per liter (M). Absorbance is a measure of the amount of light that is absorbed by a solution. It is often expressed in units of absorbance units (AU). The relationship between concentration and absorbance is described by the Beer-Lambert law, which states that the absorbance of a solution is directly proportional to the concentration of the absorbing substance and the path length of the light beam through the solution.
The Beer-Lambert law can be used to determine the concentration of a substance in a solution by measuring the absorbance of the solution at a specific wavelength. This technique is often used in analytical chemistry to determine the concentration of unknown substances in solution.
