How to Read a Gas Chromatograph

  • Print this article

Gas chromatography is used to analyze compounds that can be vaporized without breaking down into simpler compounds. It's a common technique in analytical chemistry and is typically used to determine the purity of a substance. A gas chromatograph (GC) essentially tells you the time that a component separates (elutes) from the sample, assuming the GC is able to detect it. The GC then produces a graph, which an analyst must interpret.

Things You'll Need

  • Sample compound
Show More

Instructions

    • 1

      Examine the form of the chromatographic data. The output of a GC is called a chromatogram and is generally a two-dimensional graph. The amount of detector response is measured on the y-axis, and the retention time is measured on the x-axis.

    • 2

      Study the chromatogram. It will show a spectrum of peaks, where each peak represents an analyte in the sample. The retention time can help identify an analyte under the proper test conditions.

    • 3

      Learn as much as you can about the sample. The analyst generally must have some idea of what components are in the sample in order for the chromatogram to be meaningful. Even with this information, a component may not be detected if the sample contains another component in a higher concentration with the same elution time.

    • 4

      Connect the GC to a mass spectrometer. While the pattern of peaks can be used to identify analytes directly, a GC normally provides its results to a mass spectrometer or other detection device. This detector then identifies the analyte that's represented by each peak.

    • 5

      Determine the amount of each analyte shown on the chromatogram. GC analysis uses integral calculus to calculate the area under each peak curve. This value is proportional to the original concentration of each analyte in the sample.

Related Searches

References

Comments

You May Also Like

  • How to Use a Gas Chromatograph

    Gas chromatography is a technique used in chemistry to analyze the components of a sample compound. ... How to Read a Gas...

  • How to Troubleshoot a Gas Chromatograph

    How to Read a Gas Chromatograph; How to Troubleshoot the Gas Ignition on a Dometic RV Refrigerator; How to Install a GC...

  • How to Calculate GC Response Factors

    Fit a straight line to the data by using the calculator graph function and ... How to Read a Gas Chromatograph. Gas...

  • How Do I Test for Propylene Glycol in Water?

    Gas chromatography can be used to determine a water sample's propylene glycol content. ... Present the graph to a chromatography analyst.

  • How to Calculate HPLC Resolutions

    Other People Are Reading. How to Calculate Theoretical Plates; How Is Resolution Measured? Print this article; Things You'll Need. ... In paper...

  • How to Measure Signal to Noise for HPLC

    Other People Are Reading. ... Measure the vertical distance on the graph between the bottom and top of the noise band. ......

  • Gas Chromatographic Techniques

    How to Read a Gas Chromatograph. Gas chromatography is used to analyze compounds that can be vaporized without breaking down into simpler...

  • Gas Chromatograph Facts

    How to Read a Gas Chromatograph. Gas chromatography is used to analyze compounds that can be vaporized without breaking down into simpler...

  • How to Read Graphs & Charts

    Most graphs and charts are easier to read if you look at them in terms of rows and columns. Though the lines...

  • How to Identify Unknown Peaks in Chromatography

    In gas chromatography, ... Other People Are Reading. How to Read a Gas Chromatograph; How to Calculate RRT; Print this article; Things...

  • How to Measure Ethylene Gas Production

    Using gas chromatography, it is possible to test the rate at which a sample of fruit produces ethylene. Other People ... How...

  • How to Measure Hydrogen Sulfide

    A gas chromatograph can measure H2S levels by separating and measuring the individual compounds of a gas sample. Other People Are Reading....

  • Instrumental Methods of Analysis

    In gas chromatography (GC), the sample is diluted in solvent, then injected into a heated chamber where it vaporizes. ... How to...

  • How to Read Graphs

    Graphs are visual representations of data used to organize and demonstrate relationships. The three basic types of graphs taught early in math...

  • How to Use a Gas Analyzer

    Read this Article in UK English; Photo Credit Oxygen image by JASON WINTER from Fotolia.com; More Like This. ... How to Use...

  • How to Calculate Theoretical Plates

    Chromatography is a method of substance separation. ... Obtain a chromatogram chart from your chromatographic column. 2. ... How to Read a...

  • Food Chemistry Testing

    Food chemistry testing includes aroma analysis, flavor chemistry, texture analysis, ... The gas chromatograph produces a chart, called a chromatogram, ...

  • How to Measure the Chromatogram Dye

    Liquid chromatography is an analytical tool used to identify chemicals or dyes based on their size or structure. ... Other People Are...

  • How to Install a GC Column

    A GC column is an important part of compound separation when performing gas chromatography. ... used for chemical analysis. ... chart is...

  • What Are the Advantages of HPLC Over GC?

    Springerlink: Liquid Chromatography Will Not Replace Gas Chromatography; Resources. Read this Article in UK English; ... Gas chromatography (GC) ...

Related Ads

Featured
View Mobile Site