a. Any of a large class of sour-tasting substances whose aqueous
solutions are capable of turning blue litmus indicators
red, of reacting with and dissolving certain metals to form salts,
and of reacting with bases or alkalis
to form salts. b. A substance that ionizes
in solution to give the positive ion of the solvent. c.
A substance capable of yielding hydrogen ions. d. A proton
donor. e. An electron acceptor. f. A molecule or ion
that can combine with another by forming a covalent
bond with two electrons of the other.
Excerpted from The American Heritage Dictionary of the English Language, Third
Edition Copyright © 1992 by Houghton Mifflin Company. Electronic version
licensed from Lernout & Hauspie Speech Products N.V., further reproduction
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