Potassium Analysis by Atomic Absorption

Introduction

K exists primarily as silicate in the earth's crust. Moreover, it is present at about 400ppm in sea water, which is about 1/30 of the concentration of Na This difference is due to the fact that while Na⁺. passes as it is from the weathering of rocks into the oceans, K⁺. adheres to colloidal substances from the earth's crust to be absorbed by plants, so that only a small amount flows into the oceans. K obtained by electrolysis of melted KOH or KCI is a silver white soft metal which explicity wate to ignite sins it red is petroleum. Since K forms the superoxide KO₂ and is abundantly reactive, it is different from Na, another of the alkali metals. Compounds of K include KNO₃, which is used as an oxidant in matches and fireworks, etc., KOH, a soap, K₂CO₃, a raw material in glass, and KCI, used in fertilizer formulations. K is involved in various physiological functions, such as protein synthesis, intra- and extra-cellular water transport and signal transmission, and is an essential element for living organisms. K is present in the human body at about 2g/kg, with concentrations in muscle at about 16,000ppm and blood at about 2100ppm. Food-contained K is absorbed in the small interseted trom the kidin, and the remainder via te cas matter and perspiration. It is thought that K deficiency almost never occurs due to the action of homeostasis, however, K deficiency brought about by extreme diarrhea or vomiting can cause symptoms such arrhythmia. On the other hand, when uremia or urinary tract blockage occurs, hyperkalemia can result, causing arrhythmia or other abnormalities on electrocardiograms. KCh is used as a supplement for K, in Ringers solution (1L containing 8.6g NaCl, 0.3g KCI, 0.33g CaCl₂), and in various medicinal drugs, such as in diuretics, etc. We introduce here the differences and utilization of the peak height method and peak area method for signal processing in furnace analysis of K as an example.

November 25, 2005 GMT