Question

in synthesizing ethyl acetate by fischer esterification a Vernier Mini GC will be used. the GC uses a metal column with a nonpolar coating and atmospheric air as the mobile phase, in addition, the temperature of the GC can be varied. under these conditions, what component will show up first in your chromatogram? ethyl, acetic acid or ethyl acetate?

Answer 1

The mobile phase is atmospheric air, the stationary phase is a metal column with a nonpolar coating. Means stationary phase is nonpolar. Thus the stationary phase will interact with the nonpolar component of the mixture in extent and make it run slower than that of others. Polarity order of the components of the mixture is

Acetic Acid > ethanol > ethyl acetate.

Thus in the chromatogram, we will see acetic acid first as it is the most polar component and it will least interact with the stationary phase.

Whereas, ethyl acetate will show at the last because it is a least polar component and will most interactive with the stationary phase.