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

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Chocolate contains fat in the form of stearic acid.

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That acid confers elegance on wine, a kind of zappy joy, a form of energy?

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Coal contains high amounts of acid producing sulphur that degrades and poisons the catalytic reformation beds used to form the syngas back into liquid fuels.

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Amino acids link together to form a protein when the amine group on one reacts with the acid group on the next.

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PLAs are formed when molecules of lactic acid (which is obtained, in this case, from maize starch) join together to form long chains.

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But 0.2% of the children whose mothers did not take folic acid had autism, compared to 0.1% of the children of mothers who took the vitamin in pill form.

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