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Gas Chromatography

In: Science

Submitted By blaine
Words 534
Pages 3
Objective: Analyzing three of the fraction samples from the previous lab: “Separation, Extraction, Fractional Distillation & Gas Chromatography” to determine the contents purity

Equations: Area of peak=1/2HxW % composition= (Area of peak/Total area of peak(s)) x 100

Properties: Diethyl ether 1,2-dimethoxy ethane
Formula C4H10O3 ClCO(CH2)8COCl
Melting Point −116.3 °C -58°C
Boiling Point 62 - 64 °C 82 - 83°C
Density 1.005 g/cm3 1.121
Physical Properties Clear, colorless liquidSweet, ether-like odor Clear, colorless liquidSharp, ether-like odor
Hazards Extremely flammableIrritant Flammable liquid and vaporMay cause irritation to skin

1. Use a syringe to obtain 0.5uL of fraction 1
2. Insert syringe as far as possible into the Gas Chromatography (GC)
3. Quickly press plunger to release fraction sample into GC
4. Press “Start” on the integrator
5. Remove syringe
6. At the end of process, approximately 3 minutes, press “Stop” on integrator
7. Press “shift” and “enter” keys to feed paper through integrator
8. Clean syringe with cleaning solvent
9. Repeat steps 1-8 using the other fraction samples
10. Determine the percent composition to each of the fractions

Data & Results:

Glass Beads: Run Time (min) Area (%)
Fraction 1 Ether 0.7 70 1,2-dimethoxyethane 1.2 30
Fraction 6 Ether n/a n/a 1,2-dimethoxyethane 1.1 100
Fraction 10 Ether n/a n/a 1,2-dimethoxyethane 1.1 100 Raschig rings:
Fraction 1 Ether 0.76 100 1,2-dimethoxyethane n/a n/a
Fraction 6 Ether 0.73 18.5 1,2-dimethoxyethane 1.1 81.5
Fraction 10 Ether n/a n/a 1,2-dimethoxyethane 1 100

Copper Wire:
No data results were taken

§ 1st fraction for glass beads had one peak
§ 2nd fraction for glass beads had 2 peaks as expected
§ 3rd fraction of glass beads had 1 peak
§ 1st...

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