Question

The number average molecular mass and mass average molecular mass of a polymer are respectively 30,000 and 40,000. The poly dispersity index (PDI) of the polymer is

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• A. $1$
• B. $<1$
• C. $0$
• D. $>1$

Answer 1

The correct option is D $>1$

PDI (Polydispersity Index) is the ratio of the mass average molecular mass to the number average molecular mass.

Therefore,
$\text{PDI}=\frac{40000}{30000}=1.33$
Thus, PDI of the polymer is >1