phenolphthalein

noun
phe·​nol·​phtha·​lein | \ ˌfē-nᵊl-ˈtha-lē-ən How to pronounce phenolphthalein (audio) , -ˈtha-ˌlēn, -ˈthā- How to pronounce phenolphthalein (audio) \

Definition of phenolphthalein

: a white or yellowish-white crystalline compound C20H14O4 used in analysis as an indicator because its solution is brilliant red in alkalies and is decolorized by acids and in medicine as a laxative

First Known Use of phenolphthalein

1875, in the meaning defined above

History and Etymology for phenolphthalein

International Scientific Vocabulary phenol + phthalein any of various xanthene dyes, from phthalic acid

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The first known use of phenolphthalein was in 1875

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Cite this Entry

“Phenolphthalein.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/phenolphthalein. Accessed 14 Jul. 2020.

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More Definitions for phenolphthalein

phenolphthalein

noun
phe·​nol·​phtha·​lein | \ ˌfēn-ᵊl-ˈthal-ē-ən How to pronounce phenolphthalein (audio) , -ˈthal-ˌēn How to pronounce phenolphthalein (audio) , -ˈthāl- \

Medical Definition of phenolphthalein

: a white or yellowish white crystalline compound C20H14O4 that is used in analysis as an indicator because its solution is brilliant red in alkalies and is decolorized by acids and that is used in medicine as a laxative

More from Merriam-Webster on phenolphthalein

Britannica.com: Encyclopedia article about phenolphthalein

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