Polymers Question 122
Question: The mass average molecular mass & number average molecular mass of a polymer are respectively 40,000 and 30,000. The polydispersity index of polymer will be
[Kerala CET 2005]
Options:
A) < 1
B) > 1
C) 1
D) 0
E) - 1
Show Answer
Answer:
Correct Answer: B
Solution:
Average number molecular weight $ \overline{M _{n}}=30,000 $
Average mass molecular weight $ \overline{M _{w}}=40,000 $
Polydispersity index (PDI) $ =\frac{\overline{M _{w}}}{\overline{M _{n}}}=\frac{40,000}{30,000}=1.33 $
BETA
