Gibbs free energy factors affecting

Most metals tend to corrode in an environment of air and/or water, forming metal oxides or hydrated oxides. Whether or not such a reaction is possible is dictated by the thermodynamics of the corrosion reaction. If the reaction has a negative Gibbs free energy of formation, then the reaction is thermodynamically favoured. While thermodynamics determines whether a particular reaction can occur or not, the rate of the corrosion reaction is determined by kinetic factors. A number of variables can affect the corrosion rate, including temperature, pH and passivation, which is the formation of a thin protective film on a metal surface. Passivation can have a tremendous influence on the corrosion rate, often reducing it to a negligible amount. 

It was shown in the previous chapters that the behavior of bound water is affected by many factors, which could be elucidated from comparison of the results obtained such methods as low temperature NMR spectroscopy, TSDC, DSC, adsorption, and quantum chemical modeling. The NMR, TSDC, and DSC are sensitive to transition of phase water-ice and can distinguish different phases in terms of quantity. These methods allow obtaining structural information on interfacial water (UWCSD), pore structure (PSD, surface area, and volume of pores in different ranges), and the thermodynamic characteristics of bound water or other liquids (such as changes in Gibbs free energy... 

The rate of crystal growth is dependent on two factors temperature and molecular weight. Temperature affects the growth and formation of crystals due to the Gibbs free energy. Gibbs free energy can be defined as... 

Gibbs notes that for macroscopic crystals, the free energy associated with the volume of the crystal will be larger than changes in free energy, due to departures from its equilibrium shape. For these crystals, their shape will depend on kinetic factors, which are affected by crystal defects, surface roughing, and impurities in the solvent. 

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