Emma Sullivan
Mr. Sousa
Organic Chemistry
17 Jan 2015
Chromatography: Midyear Project
Introduction:
Chromatography in a simplistic definition is a broad range of physical methods used to separate organic or inorganic substances so that they can be analyzed and studied. By studying the substances, they can figure out what makes up the compound even though they may appear homogenous. The components being separated go through two phases called stationary phase and mobile phase. The mobile phase flows through the stationary phase and carries the components of the mixture with it. At different points of the stationary phase, components will be absorbed and stop moving with the mobile phase which is how the results are recorded (the point at which…show more content… The components of a sample are dissolved in a solvent and vaporized to be separated by the stationary and mobile phase. In this case, the mobile phase would be an inert gas that would carry the molecules of the substance through the heated column and the stationary phase is either a solid absorbent, termed GSC, or a liquid GLC. Gas chromatography is the sole form of chromatography that doesn’t use the mobile phase for interacting with the substance being analyzed. Gas chromatography results are displayed in the form of a graph with different peak heights and widths corresponding to the substance they represent. Each peak is characterized by the retention time, identity of the component in the mixture, and percent composition of the component within the mixture. Below is an example of how the peaks are calculated as well as a sample…show more content… Retention factor is defined as the distance traveled by a compound divided by the distance traveled by a solvent. The distance traveled by the compound is the measure from the origin of the substance to the new position of the compound. The distance traveled by the solvent is the origin to the solvent front, which is the distance it travels (shown above labeled by line segments a and b). One example of gas chromatography use is separating a mixture of isomeric butyl alcohols and find the percent composition of each component. One example of liquid chromatography is the separation of pen ink and an example of paper chromatography is the separation of the pigments found in leaves. The aim of qualitative chromatography is to find out what’s in the sample. Once the contents are identified, quantitative is how much of each is in within the same. Quantitative is known as the analysis of qualitative. Chromatography, in general, comes in various techniques and is widely relied upon by scientists of all