In the absence of water, there are fewer restrictions on the nature of ionic metal species that can exist in an electrolyte. Ions with high valencies can comproportionate with low valent species to form stable intermediate oxidation states. In the case of alloy electrodeposition, the initial oxidation states of the metals in the system may change spontaneously if a red-ox reaction between different ions is possible. Without the passivating effects of oxygen or water, the surface of the anode remains chemically active and can be attacked by ions with more positive reduction potentials. H~+ ions, if present, can participate in the oxidation of some species, forming hydrogen gas that leaves the system. Examples of red-ox reactions in selected ionic liquid electrolytes and some proposed methods of taking these processes into account are discussed.
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