ENCH 213 Lecture Notes - Monochrome, Ion, Pyrrolidine

• School: Queen's University
• Department: Chemistry
• Course: ENCH 213
• Professor: Diane Beauchemin

Document Summary

Flame atomizer combustion of a fuel/oxidant mixture temperature varied by changing fuel/oxidant ratio (i. e. their flow rates) Rich flame = relatively rich in fuel: excess carbon reduces formation of mo, moh. Lean flame = excess oxidant: hotter than rich flame organic solvent in sample may act as additional oxidant or fuel, depending on the solvent. A rich flame in atomic absorption spectroscopy would: decrease the concentration of metal oxides in the flames, be hotter than a lean flame, be preferred for refractory elements. Flame atomizer flame chose according to: analyte and the nature of matrix most common. Flame selection air/acetylene: lower t, favors neutral atoms, path length = 10 cm, n2o/acetylene, higher t, may favor excited atoms, path length = 5 cm, watch out for explosion! Other possible problems vaporization or chemical interference: formation of refractory compound (stable, hard to break into atoms) with so4. (aq) ca3(po4)2: suppression of analyte signal, ex: suppression of mg signal by al.