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NEET levelSingle correct optionDifficulty 1 of 3pl119

The polydispersity index (PDI) of a polymer sample is defined as

A $M_{w} - M_{n}$
B $M_{w} \times M_{n}$
C $M_{w} / M_{n}$
D $M_{n} / M_{w}$

Answer: C

By definition

PDI = M_{w} / M_{n}

, where

M_{w}

is the weight-average and

M_{n}

the number-average molar mass.

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