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JEE Advanced levelOne or more correct optionsDifficulty 3 of 3pl045

A sample has 1 mol of chains of $10000 g mo l^{- 1}$ and 1 mol of chains of $30000 g mo l^{- 1}$ . Which are correct?

A $M_{n} = 20000 g mo l^{- 1}$
B $M_{w} = 25000 g mo l^{- 1}$
CPDI $= 1.25$
D $M_{n} = 25000 g mo l^{- 1}$

Answer: A, B, C

M_{n} = (10000 + 30000) /2 = 20000

.

M_{w} = (1000 0^{2} + 3000 0^{2}) / (10000 + 30000) = 25000

. PDI

= 1.25

. The value 25000 is

M_{w}

, not

M_{n}

.

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