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12.2 g of benzoic acid (Mw=122) in 100 g...

`12.2 g` of benzoic acid `(Mw=122)` in `100 g` benzene has depression in freezing point `2.6^(@)`, `K_(f)=5.2^(@) kg mol^(-1)`. If there is ``100%` polymerzation, the number of molecules of benzoic acid in associated state is

A

1

B

2

C

3

D

4

Text Solution

Verified by Experts

The correct Answer is:
B
`m`=(benzoic acid)
`=(1000K_(b)W_(1))/(DeltaT_(b)W_(2))`
=`244` (twice of actual molecular weight)
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