This is drawn into the engine, compressed and mixed explosively with a small amount of hydrogen.

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Bees also secrete an enzyme that adds a small amount of hydrogen peroxide.

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Like alcohols, fatty acids are molecules that have lots of hydrogen and carbon atoms, and a small amount of oxygen (in their case two oxygen atoms, rather than one).

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Chemical companies today create hydrogen by cracking methane, a process that results in a tremendous amount of greenhouse gases.

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It has found ways to reduce the amount of platinum and other exotic metals needed to combine hydrogen and oxygen.

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The problem is that the amount of energy required may significantly exceed that which the hydrogen can subsequently be used to generate.

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The gas is then fed into a stack of solid oxide fuel cells, where a chemical reaction between hydrogen and oxygen occurs, producing electricity, water vapor and a tiny amount of carbon dioxide.

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"Fueling is particularly difficult because the amount of money that would have to be put in to get hydrogen generated at filling stations is very costly and would require cooperation from everyone from the automaker to the government to the fueling station owners, " See said.

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Extracting platinum from this dust (e.g. for use in fuel cells for hydrogen cars), which originates in catalytic converters, might prove lucrative and would expand the limited amount of platinum available, which does not meet even present demand for it.

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