Please help me with the question below. A detailed explanation to aid in understanding is welcome. Calculate M, M, and the polydispersity index for a hypothetical polymer sample that contains equimo-lar amounts of polymer having molecular weights of 30,000, 60,000, and 90,000.

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Answered: Calculate M, M, and the polydispersity…

Macroscale and Microscale Organic Experiments

7th Edition

ISBN:9781305577190

Author:Kenneth L. Williamson, Katherine M. Masters

Publisher:Kenneth L. Williamson, Katherine M. Masters

Chapter4: Recrystallization

Section: Chapter Questions

Problem 1Q

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Explaining the following polymer size fractions in a polymer sample: Fraction Molecular Weight Number of Chains 1 3,250 400 5,000 500 3 500,000 4 а. Calculate the number-average molecular weight of the polymer. b. Calculate the weight-average molecular weight of the polymer. c. Which average molecular weight did the 4 chains of molecular weight of 500,000 most significantly affect? why ? d. Calculate the polydispersity index (PI = (Mw/Mn) of the polymer.
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Calculate M, M, and the polydispersity index for a hypothetical polymer sample that contains equimo- lar amounts of polymer having molecular weights of 30,000, 60,000, and 90,000.