Application of calorimetric methods to investigate interactions in solutions

Calorimetry is a method to measure the heat effect of a process, which could be physical changes such as melting, evaporation, dehydration (could also be defined as a chemical change) or it can be chemical changes such as acid- base neutralization, dissolving, solid-state reaction and crystal phase transition. Calorimetry is well applied in thermochemistry area by determining the enthalpy formation trends, phase stability, heat capacity, surface effect, etc.

Calorimetry is the act of measuring the heat of chemical reactions or physical changes. It also can be considered as the science of making such measurements. All calorimetric techniques are therefore based on the measurement of heat that may be generated (exothermic process), consumed (endothermic process) or simply dissipated by a sample.

Calorimetry is performed with a specially designed tool known as a calorimeter. It is a device used for calorimetry or the process of measuring the heat of chemical reactions and physical changes as well as heat capacity. Differential scanning calorimeters, isothermal microcalorimeters, titration calorimeters and accelerated rate calorimeters are among the most common types of it.

In the research work I am involved in, the calorimeter with variable temperature and block of reaction, which can operate in mode of dissolution or titration is used.

Molecular interactions and particularly the solute-solvent interactions significantly influence the processes and reactions that take place in a solution. For this reason they are intensively studied by means of different experimental methods. Much attention in these studies is paid to the aqueous solutions of organic compounds. Our laboratory is engaged in researching processes characteristic for non-aqueous environment.

The processes occurring in solutions are connected with the enthalpy change. Consequently, it is possible to investigate this phenomenon by means of the solution calorimetry. However, the heat effect determined calorimetrically is a sum of different energetic effects that accompany the dissolution, dilution and mixing processes. Therefore, systematic studies on selected systems and the use of appropriate model of interactions are necessary for us to obtain the interesting information from the calorimetric data.

The results of calorimetric measurements of dissolution enthalpy of different stuff in mixed solvents are discussed with regard to the intermolecular interactions that occur in the solution.

Volkova M. A.