Question

What is meaning of area of signal ?

Answer 1

I think they mean the integrand....i.e. the area under a curve....

Explanation:

It is a fundamental, unifying principle of ALL spectroscopy, that the area under the curve of a given signal, i.e. the integrand, is proportional to the NUMBER of absorbing species, i.e. and thus proportional to the number of atoms or species that GIVE RISE to that signal.

This is especially true for `""^1H` `"NMR spectroscopy"`, where the signals are routinely integrated in the basic, 1D experiment...and for an example we reproduce the `""^1H` `"NMR spectrum"` of `"1-propyl bromide"`:

Three peaks are seen in the spectrum....with an integration ratio of `2:2:3`...thus defining the 7 protons of propyl-bromide... Integration should be the FIRST thing you do with a spectrum ... it's a quantitative measurement, that aids you in the assignment of the spectrum.