Two Constitutional Isomers of Phenolphthalein Are Shown Below

question 13

Essay

Two constitutional isomers of phenolphthalein are shown below.One of them is colorless, while
the other is responsible for the characteristic pinkish hue desperately sought by beginning students
learning titration techniques.Identify which is the pink isomer, and explain how you know.

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Definitions:

IV Urography

A radiographic technique involving the intravenous injection of a contrast medium to visualize the urinary tract, including the kidneys, ureters, and bladder.

Cathartic

Refers to a substance or experience that induces a profound emotional or physical purging effect.

Soapsuds Enema

An enema solution made from a mixture of a soap and water used to stimulate bowel movement and relieve constipation.

Recombinant Human Erythropoietin

A synthetic form of erythropoietin used to treat anemia, particularly in patients with chronic kidney disease, by stimulating red blood cell production.