.A linear polyester was synthesized from a mixture of diacid and glycol with carboxyl to hydroxyl ratio greater than unity. A sample of the polyester (3.5 g) requires titration with 23 mL of N/50 KOH to reach a phenolphthalein end point. By vapor-pressure osmometry the molecular weight of the polymer was determined to be 12,000. Calculate the average carboxyl functionality of the polymer (that is, average number of carboxyl groups per polymer molecule).

.A linear polyester was synthesized from a mixture of diacid and glycol with carboxyl to hydroxyl ratio greater than unity. A sample of the polyester (3.5 g) requires titration with 23 mL of N/50 KOH to reach a phenolphthalein end point. By vapor-pressure osmometry the molecular weight of the polymer was determined to be 12,000. Calculate the average carboxyl functionality of the polymer (that is, average number of carboxyl groups per polymer molecule).

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter31: Synthetic Polymers

Section31.SE: Something Extra

Problem 33AP

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