The Reasons for Using Thermal and Calorimetric Methods

Novice analysts may enquire why yet another technique is needed when gas chromatography, molecular and atomic spectrometry and electrochemical analysis plus many other powerful analytical tools are available. The answer might best be given by considering two practical examples. 

how can you analyse a mixture of processed minerals such as a cement Although X-ray diffraction might tell you the different minerals present and atomic absorption spectrometry could measure the elements quantitatively, this does not help to analyse how the cement would behave in practice. For this we need to compare the behaviour under conditions of mechanical and thermal stress and the thermoanalytical techniques of TG, DTA and TMA are important tools for doing this.  

Second, the preparation of new chemicals for new pharmaceutical products, synthetic materials and foods could add to the hazards which workers and customers face. Thermal instability and explosive behaviour can be extremely destructive and costly events. Reaction calorimetry and similar techniques can help to predict the likely behaviour of chemicals when reactions, transport and storage are concerned. Physiological behaviour may vary with the nature and form of a drug, and the nature and interconversion of these forms is often studied by thermal and calorimetric methods. 

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