Red 40 Dye Experiment

For this experiment, a few scientists are researching how different flavors/colors of sports drinks effect the amount of red 40 dye in each drink. The independent variable in the experiment is the flavors of Gatorade (a brand of sports drinks) used, while the dependent variable is the concentration of dye the sports drinks contain. The constant variable is the spectrophotometer, the amount of liquid used, and the same type of cuvette. The controlled variable is only using water. In order to determine which drink would have the greatest concentration of red 40 dye, the scientists must first understand what it actually is. Red 40 dye - often known as Allura red, Food red 17, and even C.I. 16035 - is a petroleum-based substance that comes from naphthalene and dark red powder. It is a very cheap artificial dye, allowing it to be added into over 40% of food each year. Because of this, it can be found in unnaturally red …show more content…
This law states that the absorbance of a substance is directly proportional to the concentration of the absorbing substance. The formula for Beer-Lambert law is A=abc. “Where A= absorbance (unit-less); a=molar absorptivity (molarity -1 • cm 1), which is a constant for the absorbing substance, b= path length or thickness of the absorbing layer of a solution (cm), and c=concentration of the solution (molarity).” (Schmidt, 2015). In this experiment the scientists will measure the amount of Red 40 dye in sports drinks by using a spectrophotometer which consists of a circuit that has a white LED (light emitting diode) light and a photoresistor or light detector. A spectrophotometer measures light absorption. The scientist will be using this tool to create a calibration curve, test the wavelength and resistance of each sports drink, and by using the absorption spectrum they will measure the amount of Red 40 dye in each sports