ABSTRACT
If a reaction between two substances shall be started or accelerated, the chemist’s first choice is increasing the temperature of the carefully mixed reactants. This is true as well both for liquids or solutions of solids (where a good contact between the reactants is made by stirring) and for mixtures of solids. In each case, a precondition for understanding the processes occurring in the mixed system is to know the behavior of the participating individual compounds under heating. These substance or system properties are summarized under the term thermal behavior; they are investigated and described by the various methods of thermal analysis (TA). The complete definition of this multitude of physicochemical measuring methods can serve the following. TA means to follow the changes of one or more physical parameters of a sample subjected to a controlled temperature program as functions of temperature or time (Feist 2015). This definition acknowledges that in many (not in all) cases, the temperature-dependent property changes can characterize a phase as unequivocally as its chemical formula or structure. TA methods determine properties; they do not represent a kind of structure analysis, even if knowing the structure (mostly the crystal structure) practically always favors or enables the interpretation of thermal processes.
