Question

1. A student accidentally injected 0.1 uL of 2-butanone instead of ethanol to a mini GC. In an effort to

fix the mistake, the student immediately hit the “Stop Collect” button on Logger Pro and

then proceeded to inject ethanol instead. The student then hit the “Collect” button and

was surprised to see two peaks on the resulting chromatogram instead of just one.

Explain what happened and how the student should have dealt with the situation.

Answer 1

The student got two peaks because the GC run was not started and 2-butanone was there in the injecting bulb. Which was mixed with ethanol and then GC run was completed. Hence he got two peaks, one for 2-butanone and another for ethanol.

He should complete full GC run after injecting 2-butanone and then he should inject ethanol. Then the above mentioned problem should not come.