BEERS LAW
1. Key Takeaways: Beer's Law Beer's Law states that the concentration of a chemical solution is directly proportional to its absorption of light. The premise is that a beam of light becomes weaker as it passes through a chemical solution. The attenuation of light occurs either as a result of distance through solution or increasing concentration. Beer's Law goes by many names, including the Beer-Lambert Law, Lambert-Beer Law, and Beer-Lambert-Bouguer Law. 2. Equation for Beer's Law Beer's Law may be written simply as: A = εbc where A is absorbance (no units) ε is the molar absorptivity with units of L mol-1 cm-1 (formerly called the extinction coefficient) b is the path length of the sample, usually expressed in cm c is the concentration of the compound in solution, expressed in mol L-1 Calculating the absorbance of a sample using the equation depends on two assumptions: The absorbance is directly proportional to the path length of the sample (the width of the cuvett...