Analysis in Rain Water: Potassium (KCl) and sodium (NaCl), Calcium and Magnesium, Ammonium
Analysis of potassium (KCl) and sodium (NaCl), in Rain Water:With appropriate filters and standard solutions made from known concentrations of potassium (KCl) and sodium (NaCl), it is possible to determine Na+ and K+ directly using a flame photometer.
Analysis of Total Calcium and Magnesium in Rain Water: By using ethylene diamine tetraacetic acid (EDTA) in compleximetric titration, the total Ca+Mg can be determined. The trade name “Versenate” or “Trilon” refers to EDTA’s strong complexing power with metal ions, especially alkaline earth metals, in a specific order that depends on the complex’s dissociation constant. In a conical flask, 10 milliliters of the water sample were pipetted out. When the color changed from wine red to blue, 5 ml of buffer solution (pH 8–10) and 5–6 drops of Erichrome Black-T indicator were added. The mixture was then titrated against a standard Na-EDTA solution.
Analysis of Calcium in Rain Water: Murexide indicator compleximetric titration is another method for determining calcium. Five milliliters of a 16% NaOH solution and two to three crystals were put to a conical flask containing ten milliliters of aliquot. After adding 40–50 mg of murexide indicator powder to the solution, the color progressively changed from orange to reddish violet (purple) when titrated against a 0.01 N EDTA solution.
Analysis of Ammonium in Rain Water: The fundamental procedure is to react an NH4 +-containing sample with phenol at a high pH (11.5–12.0) with oxidizing agents to produce a blue hue (Harwood and Kuhn, 1970), the intensity of which is proportional to the amount of NH4 + in the sample.Five milliliters of the sample were pipetted into a 25 milliliter volumetric flask. In the flask, 1 milliliter of EDTA solution (0.01 N) was added, stirred, and let to stand for at least one minute.. Four milliliters of the buffered hypochlorite reagent were added after two milliliters of the phenol nitropruside reagent. Flasks were submerged in a water bath, kept at 40 °C, and given 30 minutes to develop their color after the solution had been diluted. Following the removal of the flasks from the water bath and a 10-minute cooling period at room temperature, the absorbance of the colored complex was measured at 636 nm in relation to a reagent blank solution, NH4 + concentration in the samples was calculated using a standard curve derived from the analysis of a standard working solution of (NH4)2SO4.