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    Chromatography

    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, 2024, 2:12 am ad1c9bdddf

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    Chromatography of River Water

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    Reversed-phase liquid chromatography Questions

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    The Interpretation of Gas Chromatograms

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    Detector Sensitivity

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    Surface Acidity and Fluorine-Doping

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    Reverse-Phase HPLC

    Choose any type of chemical analyte in a food product and please describe in detail how to analyze the analyte using a reverse-phase HPLC. Please include sample preparation, extraction and indicate what mobile phase, column, and detector were used.

    GC peak area problem

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    HPLC-PAD

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    Gas Chromatography

    Please help with the following problem: Refer to the GLC traces given in Figure 6.16. These are analyses of the various fractions collected during the fractional distillation of the mixture of cyclohexane and toluene. The weight and mole correction factors (flame ionization detector) for cyclohexane are 0.84 and 0.78, respec

    Solubility of Organic Compounds Lab Report

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    Organic chemistry pre-lab questions

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    Size Exclusion Chromatography and SDS-PAGE

    Describe whether, and how, size exclusion chromatography and SDS-PAGE can be used to determine the molecular weight and oligomeric status of a protein. Indicate whether it is necessary to compare the protein's mobility relative to standards of known molecular weight.

    Chromatography

    Consider immobilized metal affinity chromatography, such as a Ni2+ column. For this type of chromatography, describe the basis of separation of the protein components. Why do the proteins of interest bind to the resin and how are solvent conditions changed to promote elution?

    Myoglobin and Hemoglobin HPLC

    I conducted HPLC analysis of myoglobin and hemoglobin using a C18 and C4 column. Both proteins were in a buffer solution only. On the C4 column the order of the peaks was a reverse of the C18 column. The chromatographic output showed two peaks. Looking at the UV absorbance, I can attribute one of the peaks to the heme group (

    Protein Purification Questions

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    High-performance liquid chromatography

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    Questions about HPLC Lab

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    Quantitative Analysis : HPLC Chromatographs and Beer's Law

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    Combined Gas Law and Mixtures of Gases

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    NMR Spectrum of Caffeine and Vapor Pressure of Sublimation

    A. How many peaks would you expect to fin in the NMR spectrum of caffeine? B. What characteristic absorptions of bands would you expect to find in the infrared spectrum of caffeine?And show the infrared spectrum C. the vapor pressure of 1,2-dipheneylethane, p-dichlorobenzene, and 1,3,5-trichlorobenzene are 0.06, 11.2,

    Gas Chromatography Questions

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    Column Chromatography Layers

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    Why Didn't my Chromatography Experiment Work Properly?

    I did a lab on column chromatography and thin layer chromatography, and our sample was a spinach extract. I am trying to figure out if there is a correlation between the partition coefficient and the Rf used in thin layer chromatography. Is there one? For the column chromatography we used a 9:1 hexane: acetone, thenn 1:1 h

    Conversion of formalin to a solution of methanol

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    Rf value on structural basis

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