Influência da origem do cloreto de potássio utilizado em extrações de amostras de solos, nos resultados de alumínio trocável

[摘要] Variable values of aluminum extracted with lN solutions of the reagent were observed. It was shown that the problem was related to some buffering of the solutions, probably due to presence of potassium carbonate, which precipitated aluminum. Acidifying and boiling of the solutions of potassium chloride minimized this problem.