Hikari said:Absorbance vs. Concentration
Gee. Let me think. What do those symbols and letters mean/stand for?Hikari said:A = Epsilon x L x c
Epsilon (ε) is the molar absorptivity or molar extinction coefficient, which is a constant that is unique to a particular substance and is used to relate the concentration of a substance to its absorbance in a solution.
To find Epsilon, you will need to plot a graph of absorbance vs. concentration for a known substance. The slope of the line on the graph is equal to the product of the molar absorptivity and the path length (b) of the cuvette. So, by dividing the slope by the path length, you can find the value of Epsilon.
Finding Epsilon is important because it allows you to determine the concentration of an unknown substance by measuring its absorbance. This is useful in various fields, such as biochemistry and environmental science, where the concentration of certain substances needs to be accurately measured.
The units of Epsilon are typically in liters per mole per centimeter (L/mol/cm), but they can vary depending on the units used for absorbance and concentration in the Beer's Law equation.
Yes, Epsilon can change for the same substance under different conditions, such as varying pH or temperature. It is important to determine the value of Epsilon for a specific set of conditions in order to accurately measure the concentration of a substance using the Beer's Law equation.