Oxygen halogen compounds reduction potentials

In general, highly halogenated aliphatic compounds have high reduction potentials, so much so that hexachioroethane is a better electron acceptor than molecular oxygen The likelihood that such compounds will be reduced in anaerobic soils is high. There is evidence that polychlorinated biphenyls buried in anaerobic river sediments very slowly undergo reductive dechlorination, but this is believed to be a microbial process (Quensen et al, 1988). 

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