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Polymerisation of Alkynes

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Question

experimentally molar mass of ethanoic acid is calculated as 120 using colligative property in benzene than 60. why

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Solution

Dear student,

The molar mass of ethanoic acid that is experimentally determined is taken in aqueous medium.
In the aqueous medium, due to very high dielectric constant of water, polar interactions between ethanoic acid molecules are not present. So, the molecules of ethanoic acid are associated with water rather than with each other.

Benzene has low dielectric constant. Due to this, ethanoic acid molecules interact with each other and form dimers in the benzene solvent. This formation of dimers of ethanoic acid results in the decrease in the molar mass of the molecule.

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