Why is it necessary to dilute samples when doing atomic absorption spectrometry??

Question

When doing an atomic absorption experiment using Pb, Cd and Zn we are required to dilute the stock solution from 1000ppm to a variety of lower ppm (0.5, 1, 2 etc). Why is this done? Why can't we juist use the initial solution?

Answer 1

If all of the light of a certain wavelength is absorbed, then no more can be absorbed after that.  Beer's Law no longer applies and you cannot estimate concentration.