Hydration thermochemical analysis

The standard reduction potentials (see Redox Potential) of the elements and their compounds have many important applied implications for chemists, not the least of which is being aware when a compound or mixture of compounds they are handling has the potential for exploding. This should be considered as a possibility when the appropriate potentials differ by more than about one volt and appropriate kinetics considerations apply. A simply predictable case is the sometimes-violent reaction of metals with acids, as illustrated in a recently produced discovery video. Redox activities of elements are most commonly (and most precisely) analyzed via thermochemical cycles such as the familiar Born-Haber cycle for the production of NaCl from Na and CI2. A similar analysis of the activities of different metals in their reactions with acids shows that the standard reduction potential for the metal (the quantitative measure of the activity of the metal) can be expressed in terms of the appropriate ionization energies of the metal, the atomization energies of the metal see Atomization Enthalpy of Metals), and the hydration energies... 

On the basis of the limited data available, Moskvin [300] has presented some generalizations of the thermodynamics of the formation of actinide ions in aqueous solutions. His analysis includes discussion of the heat capacities of triply charged actinide ions and the changes in their heat capacities on hydration and when transferred from a crystal lattice to solution. Moskvin concludes that further accumulation of thermochemical data for actinide ions, including those of americium, is one of the most urgent contemporary problems in actinide chemistry. 

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