MATHEMATICAL MODELS, TABLES AND NOMOGRAMS CONCERNING PH VARIATION CAUSED BY CHANGES IN CONCENTRATION OF FESO4.7H2O IN AQUEOUS SOLUTIONS USED AS FOLIAR FEEDING
This paper presents mathematical models, a data table and nomograms that can be used to evaluate the pH of the aqueous solution as related to the needed concentration in FeSO4.7H2O. The experiments have been carried out both for solutions in tap water (TW) with pH 7.18 and in distilled water (DW), for comparisons. The pH determinations have been done at 0, 6, 24, 48 and 72 h after the preparation of the solutions, because pH decreases with time. The pH decreases with the increase of the concentration (from 0 to 5%) in both types of solutions (DW and TW). At 0 h after preparation, the pH decreases from 7.18 to 3.96 in TW and reaches 3.52 in DW; at the same concentration, the pH decreases with time, so after 72 h, at 5% increase in concentration pH ends near 2.81 (extremely acid), both in TW and DW. The pH in DW solutions is lower than in TW, but the difference reduces with the increase of the concentration. The mathematical models have been statistically validated and they fit excellent to the analytic data.
Budoi , G. and Badea, E. (2012). MATHEMATICAL MODELS, TABLES AND NOMOGRAMS CONCERNING PH VARIATION CAUSED BY CHANGES IN CONCENTRATION OF FESO4.7H2O IN AQUEOUS SOLUTIONS USED AS FOLIAR FEEDING. Acta Hortic. 926, 449-456
modeling, pH, iron sulfate, aqueous solutions, foliar fertilizers