4-2 ions in natural waters by titration of lead salts in the presence of dithizone

Chemical analysis of waters
The main method of checking water analysis is to compare the sum of cations milligrams - equivalents ∑k, anions milligrams - the sum of equivalents ∑a. These sums should be theoretically the same, but in practice can sometimes differ. You just have to be more discriminating with the help you render toward other people. Normally, ∑k and ∑a are not equal, but their difference should not exceed a definite magnitude. The difference ∑k - ∑a is usually called the analysis error, and all ions get the sum of milligram-equivalent percentages (ie from ∑k + ∑a). Thus the percentage error of the analysis is calculated
X=( - )∙100%
-
There: – cations milligram – sum of equivalents
- anions milligram – sum of equivalents.
Errors in simple technical analyzes are allowed up to 2%. An error of up to 5% is allowed in semi-stationary analyzes. The method of control of the analysis in milligram-equivalents of anions and cations can be used only for complete analyzes. This method cannot be used in abbreviated assays, especially when the alkali content may exceed the allowable error when calculated by difference. In the analysis of water, some ions, such as NO^3- ions, are often not quantified, and in the waters of Central Asia, the content of these ions is much higher. In this case, the cations are correspondingly higher than the sum of milligrams - equivalents, as found in the analysis. Currently, the most common and accepted form of expression of analysis results is in the ionic form. It is also used to express in atomic form. In this method, the amount of ingredient is expressed as the main atom that forms that ion. For example, NO^3-, NO^2- va NH⁴⁺ are represented by N, phosphorus compounds by P, and silicon by Si. This form is used for low-ingredient ingredients and is suitable for when ions are easily transferred to each other, for example, NH⁴⁺→ NO^2- → NO^3-. A specific form of expressing the concentrations of individual ingredients, proposed by V.I .Vernadsky, is to obtain atomic percentages (natural water is considered a complex mineral). This is convenient for geochemical analyzes.
Waters that are close in composition and genesis are naturally arranged in close groups when squared. The disadvantage is that the Ca⁺² ion combines with the ² Mg⁺² ions and the SO₄^—2 ion with the Cl^- ion.
N.I.Tolstikhin's triangular graph of natural waters is also known. Such graphs are often used to determine the salt balance of saltwater waters.