Author: Gloria Contreras
Lab Partner: Jose Montanez
Instructor: Teresa Potter
Date Work Performed: January 13, 2015
Date Submitted: January 20, 2015
Abstract: In this lab, liquid chromatography is used to separate the Red 40 and Blue 1 dyes inside of grape flavored Kool-Aid. It was determined that the 5% isopropanol will remove the Red 40 dye from the stationary phase. The 28% isopropanol will remove the Blue 1 dye from the stationary phase. The more polar molecule is removed with the more polar mobile phase, the less polar molecule is removed with the less polar mobile phase. This is where the principle “like dissolves like,” plays a factor in the separation of the dyes. Both molecules are relatively nonpolar but the size difference is what causes Red 40 to be a more polar molecule than Blue 1 because it is smaller.
Introduction:
In this lab, liquid chromatography is used to separate the dye colors of a Kool-Aid mixture. The mixture is injected into a chromatography column, which in this lab is a C18 Sep-Pac. This is where the mixture lands on a substrate. The stationary phase may be polar or nonpolar. When a solvent is passed through the stationary phase, it will carry out the components of the same polarity. This is where the principle ‘like dissolves like,” comes into play. This principle states that a polar substance will dissolve in a polar solution and vice versa, where a nonpolar substance will dissolve in a nonpolar solution. The speed that the substance comes out depends of the polarity of the substance and how well it dissolves in the solvent. Liquid chromatography is an essential tool when trying to determine what substances are used in materials we come in contact with every day. For example, such tool can be used to determine the substances in grape Kool-Aid. Two known substances found in Kool-Aid is Red 40 dye and Blue 1 dye. These dyes have been linked to causing children to become hyperactive, and/or