Abstract
In thisy study the quantities of the inorganic ions in the precipitation of the rural area of Choongbook Province are analyzed. The sampling period of the study was between February and June of 1991. Anion concentrations were determined by ion chromatography. Metal cation concentrations were analyzed by atomic absorption spectroscopy. Nessler's reagent was used for ammonium ion. The average pH of the rain was 4.6. Occasionally, however, acidic rain of pH 3.5 was found. The ratio of anion/cation was 0.57, where the concentrations of anion was much smaller than the same of the cation. This was attributed to the high concentrations of the ammonium ion. Ion concentrations were higher in February and March than other months. Also, it was found that the $2[SO_4^{2-} + [NO_3^-]-[NH_4^+]$ gave the highest correlation with the pH values.
