Perfecţionarea metodei de preparare a soluţiei de extragere a fosfaţilor mobili şi a potasiului schimbabil din sol după metoda Macighin

Abstract

In order to prepare the extracting solution for determining mobile phosphates and changeable potassiumin the soil according to Machiginmethod, we propose to use ammonium carbonate as well as ammonium bicarbonate and ammonia water. The concentration of initial reagents and working solution should be calculated based on the equivalent mass of ion NH4 + . The solution should contain 3.27 g/dm3 NH4 + and 6.8 g/dm3 HCO3 > . Final concentration ofthe extracting solution should be of 0,182 n. ± 0,05,the pH 9.0±0.05, whichwould correspond to 1% solution prepared from standard ammonium carbonate with 31% content of ammonia.