IMPROVEMENT OF EXPERT RESEARCH OF PRECURSORS BY USING GRAVIMETRIC AND TITRIMETRIC METHODS OF ANALYSIS

Abstract

The purpose of the article is to develop a method of determining their mass fraction as a necessary and important stage of reliable forensic evaluation of research results on the basis of theoretical generalizations and practice of complex application of gravimetric and titrimetric methods of analysis on the example of three-component mixture of sulfuric and hydrochloric acids in aqueous solution. Methodology. The reliability of the obtained results and conclusions is ensured by the use of general scientific and special research methods. In particular, theoretical methods (analysis, synthesis, comparison, generalization) systematized the materials that make up the theoretical basis of the study, empirical (observation, measurement, comparison, experiment) conducted experimental studies to determine
the feasibility of using gravimetric and titrimetric methods of analysis in determining mass particles of inorganic acids. With the help of special statistical and mathematical research methods, both the mass fraction of the components of the studied mixtures and the research error were calculated. In general, the use of a set of methods allowed us to conclude that the gravimetric and titrimetric methods of analysis for determining the content of inorganic acids in ternary mixtures. Scientific novelty. The possibility of complex application of gravimetric and titrimetric methods of analysis to determine the mass fraction of two strong acids (sulfuric and hydrochloric) in aqueous solution in a threecomponent mixture as a necessary and important stage of reliable forensic evaluation of research results is substantiated. Conclusions. The complex application of gravimetric and titrimetric methods of analysis within the experiment to determine the mass fraction in a three-component mixture of two strong acids (sulfuric and hydrochloric) in aqueous solution confirmed the possibility of using them to solve expert problems. The main advantages of the proposed gravimetric and titrimetric methods of analysis are the availability of equipment, simplicity, manufacturability, high enough accuracy, indicating the feasibility of their use to determine individual concentrations of inorganic acids to address measures to control their circulation. The main principles and principles of the method of determining
the content of sulfuric and hydrochloric acids in the three-component mixture are outlined, which will serve as a basis for further development of methodological recommendations in this direction. In addition, the selection
of the main parameters of the reagents and proposed a method for quantitative analysis of individual components (inorganic acids) mixtures (solutions) – sulfuric and hydrochloric acids in a three-component mixture, based on their sequential separation and allows to obtain values of their mass fraction with relative errors 2,4 % for sulphate and
4,6 % for chloride, which is within the allowable measurement error (Δxmax ≤ 3σ).