Use Phenolphthalein in a sentence


[fee-nawl-thal-een, -ee-in, -fthal-, -nol-]
noun Chemistry, Pharmacology.
a white, crystalline compound, C 2 0 H 1 4 O 4 , used as an indicator in acid-base titration and as a laxative.

1870–75; phenol + phthalein Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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World English Dictionary
phenolphthalein (ˌfiːnɒlˈθeɪliːn, -lɪɪn, -ˈθæl-)
a colourless crystalline compound used in medicine as a laxative and in chemistry as an indicator. Formula: C20H14O4

Collins English Dictionary - Complete & Unabridged 10th Edition
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American Heritage
Medical Dictionary

phenolphthalein phe·nol·phthal·ein (fē'nōl-thāl'ēn', -thāl'ē-ĭn, -thā'lēn', -thā'lē-ĭn)
A white or pale yellow crystalline powder that is used as an acid-base indicator and as a laxative.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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American Heritage
Science Dictionary
phenolphthalein   (fē'nōl-thāl'ēn')  Pronunciation Key 
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: C20H14O4.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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Encyclopedia Britannica


an organic compound of the phthalein family that is widely employed as an acid-base indicator and as a laxative.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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Example sentences
Phenolphthalein is a presumptive test that reacts with the heme molecule present in blood.
The phenolphthalein test is used to presumptively test for the presence of blood.
My question has to do with the preparation of the phenolphthalein indicator.
Add one drop phenolphthalein solution to each standard or sample.
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