Question

How can the peak area be used to quantitatively analyze a sample using GC?

Answer 1

The area under a gas-chromatograph peak is proportional to the amount ( moles ) of compound eluted. Hence, the molar percentage composition of a mixture can be approximated by comparing relative peak areas.

You can do it by hand:

Measuring the area of a peak by geometrical approximation or triangulation.

Approximate area = h x w_1/2

h -- the height of the peak above the baseline

w1/2--the width of the peak at half of it height

This method works only when the peak is symmetrical. If the peak in unsymmetrical, it is best to cut out the peaks with scissors and weigh the pieces of paper on a analytical balance