The Factors That Affect the Intensity of Color - Lab Report Example

For this experiment a cuvette, calorimeter, and a color of your choice for the dye solution, A. To begin the experiment, clean the cuvette. Wash out the cuvette three times with water, and then three times with solution. Once the cuvette is cleaned fill the cuvette ¾ with the color solution. Once the cuvette is filled and locked. Place it in the colorimeter and read the first wavelength. Once the cuvette is filled and locked. Place it in the colorimeter and read the first wavelength. This will be the base reading that you use to determine the intensity of color in the upcoming readings. Once that is read, you can then clean the cuvette again. You will get a reading for each setting on the Calorimeter (430nm, 470nm, 565nm,635nm). You will use the lowest percentage reading and stick with that setting for the duration of the experiment. You will then start using your color solution to get readings and determine the intensity of the color.

You will begin doing this by adding more dye to the solution. You will start at 10% and work your way up to 100%. Each time you add a percentage of water to the solution you will place the cuvette into the calorimeter and read the results. Each time you finish getting the results, clean the cuvette and begin to do it again to all other percentages. The graph gives the best fit line, or the straightest line is one that predicts concentration. This graph, however, does not match the equation of Beer-Lambert’s law.

The x-axis of Beer-Lambert’s equation represents the concentration while the y-axis represents the absorbance. Lambert-Beer Law is used to determine concentration [M, mM, or mM] from Absorbance [No unit] if the molar extinction coefficient e [M-1cm-1] of a compound and the path length of the cuvette [cm] that the distance light passes through the solution are known. The formula of this relationship: The possible limitations of spectroscopy used in this investigation are the narrowness of spectra and the effect of stray radiations that might have made the measurements of absorbance upon slit width and wavelength setting and the fact that it is not possible to know the molecular weight of substance could also affect the investigation.