JEE Main levelSingle correct optionDifficulty 2 of 3pl039
Which sample is expected to have a polydispersity index closest to 1?
APolystyrene made by free radical polymerisation
BLDPE from a high pressure reactor
CA purified sample of a protein such as haemoglobin
DNatural rubber latex
Answer: C
A natural protein has a defined sequence and chain length for all molecules, so it is essentially monodisperse. Synthetic and many natural polymers such as rubber contain chains of widely varying length.