Expanding thermodynamic databases using the thermodynamic difference rule (TDR). Exemplified by an application to retrieve new thermodynamic data for thorium compounds

Publication date: Available online 7 January 2020Source: The Journal of Chemical ThermodynamicsAuthor(s): H. Donald Brooke JenkinsAbstractThis paper explores the thermochemistry of thorium compounds, in particular their hydrates MpXq.nH2O and their corresponding parents, MpXq. By taking currently available thermochemical data from the literature, we use the Thermodynamic Difference Rule (TDR) to illustrate how we can retrieve new (previously missing) data without necessitating calorimetric investigation. Moreover the results obtained are likely to have a level of accuracy and precision equal to that obtained using traditional calorimetric methods yet avoiding the attendant radiochemical procedures required for safe handling of these materials. In this way, commencing with an incomplete table containing only 42 entries out of a possible 84 (i.e. 50 %), as many as 22 (i.e. 26 %) new items of data can be deduced just by using the TDR so making the Table now 76 % complete. By this purely computational route (which requires use of a simple EXCEL spreadsheet or even just a hand calculator) which can be used by non-experts quickly and easily, the new data can be estimated and the database so expanded. The TDR Rule can also be used to validate already available, existing data. This approach represents a new and improved method of investigation of standard thermochemical data and can be used in all branches of science, not necessarily areas involving the handling of radioactive materi...
Source: The Journal of Chemical Thermodynamics - Category: Chemistry Source Type: research