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acid rain

(Encyclopedia)acid rain or acid deposition, form of precipitation (rain, snow, sleet, or hail) containing high levels of sulfuric or nitric acids (pH below 5.5–5.6). Produced when sulfur dioxide and various nitro...

rain

(Encyclopedia)rain, precipitation in liquid form. It consists of drops of water falling from clouds; if the drops are very small, they are collectively termed drizzle. Rain plays a key role in the hydrologic, or wa...

rain forest

(Encyclopedia)rain forest: see forest.

rain tree

(Encyclopedia)rain tree, also called monkeypod, a large leguminous tropical tree (Albizia saman or Samanea saman) of tropical America belonging to the family Leguminosae (pulse family), the leaves of which fold tog...

nitric acid

(Encyclopedia)nitric acid, chemical compound, HNO3, colorless, highly corrosive, poisonous liquid that gives off choking red or yellow fumes in moist air. It is miscible with water in all proportions. It forms an a...

lipoic acid

(Encyclopedia)lipoic acid: see coenzyme.

lactic acid

(Encyclopedia)lactic acid, CH3CHOHCO2H, a colorless liquid organic acid. It is miscible with water or ethanol. Lactic acid is a fermentation product of lactose (milk sugar); it is present in sour milk, koumiss, leb...

acetylsalicylic acid

(Encyclopedia)acetylsalicylic acid əsētˌəlsălˌĭsĭlˈĭk [key], acetate ester of salicylic acid. See aspirin. ...

acetic acid

(Encyclopedia)acetic acid əsēˈtĭk [key], CH3CO2H, colorless liquid that has a characteristic pungent odor, boils at 118℃, and is miscible with water in all proportions; it is a weak organic carboxylic acid (s...

methanoic acid

(Encyclopedia)methanoic acid, IUPAC name for formic acid. ...