Inorganic sources

Name three principal inorganic sources of oxygen atoms that are commonly available in the inanimate environment and readily accessible to the biosphere. 

The electrochemical reduction of carbon monoxide also offers a route for the production of fuels from inorganic sources. For example, carbon monoxide is formed from coal in gasification... 

Bare metal cations can be prepared from almost any inorganic source as long as enough energy is given to the sample to allow dissociation, vaporization, and ionization. Metal anions are less well studied due to the low electron affinities of most transition metals. Where M+ and M ions are compared, the M ions are generally less reactive. 

Recent work by Wilson Orr ( ) and others using stable isotope techniques has provided strong evidence that incorporation from an inorganic source is the most probable explanation. Inorganic sulphur (sulphate) tends to be richer in the heavy sulphur isotope, compared with reference meteoritic sulphur... 

Autotroph An organism that can synthesize its own food—complex organic compounds— using simple inorganic sources, such as carbon dioxide... 

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