Atomic Absorption Spectra of Europium, Thulium, and Ytterbium Using a Flame as Line Source

Experiments showed that atomic absorption spectra of analytical utility can be observed for Eu, Tm, and Yb using the flame as the line source. The four possible combinations of oxyacetylene and oxyhydrogen flames, as source and absorbing flames, were investigated to ascertain which gave the greatest absorption sensitivity. For oxyhydrogen flames, a nearly stoichiometric oxygen and fuel mixture was found to maximize both emission and absorption but extremely fuel-rich oxyacetylene flames were required to observe optimum emission and absorption. Preliminary investigations showed that sodium and calcium can easily be determined at concentrations less than 5 and 20 ppm, respectively.