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indicators, acid-base

(Encyclopedia)indicators, acid-base, organic compounds that, in aqueous solution, exhibit color changes indicative of the acidity or basicity of the solution. Common indicators include p-nitrophenol, which is color...

acid-base indicators

(Encyclopedia)acid-base indicators: see indicators, acid-base. ...

base

(Encyclopedia)base: see acids and bases.

pH

(Encyclopedia)pH, range of numbers expressing the relative acidity or alkalinity of a solution. In general, pH values range from 0 to 14. The pH of a neutral solution, i.e., one which is neither acidic nor alkaline...

acids and bases

(Encyclopedia)acids and bases, two related classes of chemicals; the members of each class have a number of common properties when dissolved in a solvent, usually water. Another theory that provides a very broad ...

base line

(Encyclopedia)base line: see geodesy.

nucleic acid

(Encyclopedia)CE5 Replication of strands of DNA CE5 nucleic acid, any of a group of organic substances found in the chromosomes of living cells and viruses that play a central role in the storage and replica...

neutralization

(Encyclopedia)neutralization, chemical reaction, according to the Arrhenius theory of acids and bases, in which a water solution of acid is mixed with a water solution of base to form a salt and water; this reactio...

Joint Base Andrews

(Encyclopedia)Joint Base Andrews, officially Joint Base Andrews Naval Air Facility Washington, formerly Andrews Air Force Base, U.S. military installation, 4,279 acres (1,732 hectares), central Md., est. 1943. It i...

index number

(Encyclopedia)index number, in econometrics, a figure reflecting a change in value or quantity as compared with a standard or base. The base usually equals 100 and the index number is usually expressed as a percent...