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    Chromatography refers to a set of physical techniques used for separating or analyzing mixtures. Preparative Chromatography focuses on the separation of chemical compounds from a mixture. This is a form of purification, where pure compounds can then be used in further experiments. Analytical chromatography focuses on the analysis of chemical mixture, usually to determine the identity of certain components, or to measure the relative concentrations of the analytes in a mixture. The process of chromatography involves dissolving the components of a chemical mixture in a fluid called the mobile phase. This carries the dissolved analytes through a specific material called the stationary phase. Depending on the identity of the analyte, the mobile phase will travel at varying speeds through the stationary phase. The speed of the specific analyte will correlate to a certain length, which is then compared to the length of the entire mobile phase to give the ‘Rf value.’ The Rf value has the formula: Rf = length of component travelled / total length of mobile phase By calculating the Rf value, identification of a chemical compound can be easily determined by calculating the speed at which it travels through the stationary phase. Thus, understanding the concept of chromatography is crucial for understanding how to separate or quantitatively analyze chemical mixtures. © BrainMass Inc. brainmass.com March 29, 2023, 3:37 pm ad1c9bdddf

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