Methyl Orange

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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Methyl Orange

 

(sodium ρ-dimethylaminoazobenzenesulfonate), a synthetic orange azo dye. It is used as an acid-base indicator in the titration with solutions of strong acids, and also to determine the pH of a medium. Methyl orange changes color from red to orange-yellow at a pH of 3.1–4.4.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.