Gas Chromatography
GAS CHROMATOGRAPHY EXPERIMENT
The purpose of this experiment is for the student:
1) to learn the general theoretical aspects of gas chromatography as a separation method,
2) to learn how to operate gas chromatographs specific to COD,
3) to become familiar with using the gas chromatograph (GC) to qualitatively identify components of mixtures,
4) to be introduced to and to interpret the quantitative data available via gas chromatography,
5) to gain insight into how the GC technique is used in the chemical industry both as a qualitative and quantitative tool.
As a means of accomplishing these objectives, we will attempt to identify the three major organic components of two different kinds of nail polish remover.
PRELAB ASSIGNMENT
Read Technique 22 in Pavia, 4th ed. Be sure that you understand the components of a gas chromatograph and the factors affecting separation. Pay particular attention to the definitions of retention time and resolution and how the GC can be used for qualitative analysis.
· Fill out a gold sheet for all compounds present in the purple nail polish remover as listed below.
· Write a procedural flow chart for the experiment.
EXPERIMENTAL PROCEDURE
Each student will be required to make at least one injection into the GC. Each student will also be a member of a group and will share information and chromatograms with other group members and between groups. All GC injections will be one micro-liter "sandwiched injections". The procedure for preparing the syringe is described below.
· Place your sample in a small test-tube.
· Rinse the syringe three times with your sample.
· Draw approximately 1 micro-liter of air into the syringe.
· Draw 2 or 3 micro-liters of your sample into the syringe with the air.
· Turn the syringe so that the tip of the needle is pointing up and expel liquid from the syringe until only 1 micro-liter of liquid remains in the syringe.
· Pull the plunger back and draw in approximately 1
The purpose of this experiment is for the student:
1) to learn the general theoretical aspects of gas chromatography as a separation method,
2) to learn how to operate gas chromatographs specific to COD,
3) to become familiar with using the gas chromatograph (GC) to qualitatively identify components of mixtures,
4) to be introduced to and to interpret the quantitative data available via gas chromatography,
5) to gain insight into how the GC technique is used in the chemical industry both as a qualitative and quantitative tool.
As a means of accomplishing these objectives, we will attempt to identify the three major organic components of two different kinds of nail polish remover.
PRELAB ASSIGNMENT
Read Technique 22 in Pavia, 4th ed. Be sure that you understand the components of a gas chromatograph and the factors affecting separation. Pay particular attention to the definitions of retention time and resolution and how the GC can be used for qualitative analysis.
· Fill out a gold sheet for all compounds present in the purple nail polish remover as listed below.
· Write a procedural flow chart for the experiment.
EXPERIMENTAL PROCEDURE
Each student will be required to make at least one injection into the GC. Each student will also be a member of a group and will share information and chromatograms with other group members and between groups. All GC injections will be one micro-liter "sandwiched injections". The procedure for preparing the syringe is described below.
· Place your sample in a small test-tube.
· Rinse the syringe three times with your sample.
· Draw approximately 1 micro-liter of air into the syringe.
· Draw 2 or 3 micro-liters of your sample into the syringe with the air.
· Turn the syringe so that the tip of the needle is pointing up and expel liquid from the syringe until only 1 micro-liter of liquid remains in the syringe.
· Pull the plunger back and draw in approximately 1