Energy, free ferrous oxide

Similarly, the phase equilibria are known with certainty, and free energy measurements are available (although not as closely spaced as one might wish) to define the ferrous oxide phase as having continuity over a wide stoichiometric range at 1000° K. The evidence is incompatible with the idea that these and other compounds owe their existence to ordering processes or are metastable with respect to discrete intermediate phases. 

The group of microorganisms known as autotrophic bacteria obtain energy from the oxidation of a variety of inorganic compounds (ammonia, nitrite, sulfide, ferrous iron, hydrogen, carbon monoxide, sulfur, thiosulfate).The free energy changes and over-all efficiencies of a number of these processes have been calculated. We may take as an example the oxidation of nitrite to nitrate performed by Nitrobacter... 

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