phenolphthalein

American  

[fee-nawl-thal-een, -ee-in, -fthal-, -nol-] / ˌfi nɔlˈθæl in, -i ɪn, -ˈfθæl-, -nɒl- /

noun

Chemistry, Pharmacology.

1. a white, crystalline compound, C 2 0 H 1 4 O 4 , used as an indicator in acid-base titration and as a laxative.

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phenolphthalein British  

/ -lɪɪn, ˌfiːnɒlˈθeɪliːn, -ˈθæl- /

noun

1. a colourless crystalline compound used in medicine as a laxative and in chemistry as an indicator. Formula: C 20 H 14 O 4

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phenolphthalein Scientific  

/ fē′nōl-thăl′ēn′ /

1. A white or pale-yellow, crystalline powder used as an indicator for acid and basic solutions. In solutions that are either neutral or basic, it is colorless, while it is pink or red in solutions that are alkali. It is also used as a laxative and in making dyes. Chemical formula: C ₂₀ H ₁₄ O ₄ .

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Etymology

Origin of phenolphthalein

First recorded in 1870–75; phenol + phthalein

Example Sentences

A chemical called phenolphthalein -- not approved by FDA -- was found in a Chinese product called Zi Xiu Tang Beauty Face & Figure Capsule.

From US News

Some of the supplements also contain another chemical used previously in over-the-counter laxative products, a dye called phenolphthalein.

From Forbes

The stock thus obtained should be fairly white, depending upon the grade of tallow used and slightly alkaline to an alcoholic phenolphthalein solution.

From Project Gutenberg

Transfer the precipitate and filter to the beaker, or precipitating vessel, dissolve the precipitate in a small excess of the standard alkali, add a few drops of phenolphthalein solution, and titrate with the standard acid.

From Project Gutenberg

The test is best made by the use of the well known alkaline tablet which is composed of a solid alkali, and the indicator, phenolphthalein.

From Project Gutenberg