acid: Quick Facts

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Photos and Videos

A slice of lemon with a strip of litmus paper resting on it; the paper has turned red, indicating an acidic reaction.

Learn about the properties of acids and bases along with the pH scale that measures them

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Topics

Nucleic acid oxyacid Amino acid phenol sulfuric acid carbonic acid sulfonic acid hydrogen cyanide phosphoric acid nitric acid coordination compound organic compound organometallic compound inorganic compound polymer ionic compound hydrate nonstoichiometric compound anhydride homologous series

Key People

Charles Gerhardt, engraving

Charles Gerhardt

French chemist

German Swedish chemist Carl Wilhelm Scheele, c. 1780.

Carl Wilhelm Scheele

Swedish chemist

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Jean-Charles Galissard de Marignac

Swiss chemist