1. What is Percent Composition from GC?

Percent composition from Gas Chromatography (GC) is a method to determine the relative amount of each component in a mixture by comparing the peak areas in the chromatogram to the total area of all peaks.

2. How Does the Calculator Work?

The calculator uses the percent composition formula:

Where:

• Peak Area — The area under the peak of interest in the chromatogram
• Total Area — The sum of all peak areas in the chromatogram

Explanation: The formula calculates what percentage of the total mixture is represented by the component corresponding to the selected peak.

3. Importance of Percent Composition

Details: Calculating percent composition is essential for quality control in chemical manufacturing, analyzing reaction products, and determining purity of substances.

4. Using the Calculator

Tips: Enter the peak area and total area values from your chromatogram. Both values must be positive numbers. The result will show the percentage composition of the component.

5. Frequently Asked Questions (FAQ)

Q1: What if my chromatogram has baseline noise?
A: Proper baseline correction should be performed before measuring peak areas to ensure accurate calculations.

Q2: Does this work for overlapping peaks?
A: For overlapping peaks, more advanced integration methods (like deconvolution) should be used before calculating percentages.

Q3: Should response factors be considered?
A: This simple calculation assumes equal response factors. For accurate quantitative analysis, response factors should be determined using standards.

Q4: What units should be used for peak areas?
A: The units cancel out in the calculation, so any consistent units can be used (mV·s, AU·s, etc.) as long as both values are in the same units.

Q5: How precise are GC percent composition results?
A: Typical precision is 1-5% relative, depending on instrument, method, and sample preparation.