Upon exposure to water and oxygen, these minerals oxidize to form acid-, iron- and sulfate-rich drainage.

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Most rock being mined has abundant iron sulfide minerals which oxidize when exposed to air and water.

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As the waste begins to oxidize (thanks to the bacteria), electrons are produced.

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If you oxidize any hydrocarbon, you generally produce heat, carbon dioxide, and water vapor, assuming a relatively pure fuel source.

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Their leads are metal and can oxidize, making them difficult to solder.

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Bacteria oxidize the organic matter and, in the process, produce electrons that run from the anode to the cathode within the fuel cell, creating an electrical current.

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The problem is that calcium, magnesium and lithium are a bit fussy and chemically quite reactive and will oxidize or stop working if they are exposed to oxygen and moisture.

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Wander into any eighth-grade science fair and you're likely to see an example of this destructive process at work - place two dissimilar metals in an electrolyte solution and one of the materials will slowly steal ions from the other, causing it to oxidize, become brittle and eventually break apart.

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