naphthionic acid

naph·​thi·​on·​ic acid

Definition of naphthionic acid

: a crystalline naphthylaminesulfonic acid made by baking a mixture of alpha-naphthylamine and sulfuric acid and used in the preparation of Congo red and other dyes; 4-amino-1-naphthalenesulfonic acid

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History and Etymology for naphthionic acid

International Scientific Vocabulary, from naphthylaminesulfonic

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Cite this Entry

“Naphthionic acid.” Dictionary, Merriam-Webster, Accessed 27 Oct. 2020.

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