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An acid is a chemical substance whose aqueous solutions are characterized by a sour taste, the ability to turn blue litmus red, and the ability to react with bases and certain metals (like calcium) to form salts.
Added 9/5/2014 1:23:42 AM
This answer has been confirmed as correct and helpful.
Confirmed by
jeifunk [9/5/2014 1:39:19 AM]