Solvation and association of ions in solutions largely depend on the dielectric properties of the solvent, the distance between ions in solutions, and temperature. This paper considers the effect of temperature on static dielectric constant (DC), dipole dielectric relaxation (DR) time, and limiting (ultimate) high frequency (HF) electrical conductivity (EC) of water and some polar solvents. In the investigated temperature range (0–370 °C), the static DC and DR time of water decrease, and limiting HF EC passes through a maximum at 250–300 °C with temperature growth. The dielectric characteristics of methanol, ethanol, and propanol behave in a similar way. It is shown that the existence of an HF EC temperature maximum is due to the different nature of the temperature dependences of DC and DR time. It is suggested that the same dependences are responsible for the presence of a maximum in the temperature dependences of the dissociation degree and the ionic product of water. The influence of non-electrolytes concentration as well as metal salts on the dielectric properties of their aqueous solutions is considered. The limiting HF EC of water determines the specific EC value of aqueous electrolyte solutions. Analysis of the absorption of microwave energy by polar solvents, as well as aqueous solutions of non-electrolytes and electrolytes, at a frequency of 2455 MHz is carried out. The optimal conditions for high-frequency heating of solutions have been established. The distance between ions in aqueous solutions of inorganic salts and in non-aqueous solutions of ionic liquids is calculated. It is shown that the maximum on the concentration dependence of the specific EC can be related to ions association.
Radiation-induced polymerization of elemental phosphorus in the presence of ionic liquids(IL) was investigated. Composition, structure, and properties of the productsphosphorus-containing polymers (PCPs)-were examined by the methods of physicochemical analysis. It was found that the structure of ionic liquid and its concentration in the media has a significant influence on the polymerization rate. Some kinetic properties of the radiation-induced polymerization process of the elemental phosphorus in the presence of ionic liquids in the mixed solvent "dimethylsulfate (DMSO)/benzene" were determined (reaction rate, effective rate constant, reaction orders).
The current epidemiological situation in the world forces the pedagogical community to switch to the use of various forms of education using distance educational technologies. One of the most difficult problems of organizing distance learning is the problem of various forms of monitoring students knowledge. The most promising area for assessing the quality of knowledge is computer testing. Based on many years of experience in the development of computer test tasks, the basic requirements for computer test tasks and for computer tests are formulated, which make it possible to increase the efficiency of their use to control students knowledge. Examples of the correct representation of answer options in tasks with a choice of answer options (in closed test tasks) are given and ways to reduce the probability of guessing the correct answer are considered. With regard to the course "General and Inorganic Chemistry", the features of the use of various forms of test tasks are analyzed using specific examples. For the organization of computer testing of first-year bachelor degree students in the course "General and Inorganic Chemistry" the Moodle system was chosen. This system has various functions for creating tests, as well as for conducting training and control testing. For the convenience of entering test tasks into the Moodle system, these tasks must be converted into GIFT format. After that, GIFT tasks are easily imported into Moodle. Examples of different forms of test items in WORD and GIFT formats are given. The Moodle distance learning system (platform) has introduced a bank of tests for the course "General and Inorganic Chemistry", which is taught to first-year bachelor degree students of the Mendeleev University of Chemical Technology of Russia. The features of using this platform for organizing computer testing when using distance and blended forms of education are shown.
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