Assertion : The molecular weight of acetic ac | vedclass

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Question

(A) Acetic acid $(CH_3COOH)$ undergoes dimerization in nonpolar solvents like benzene due to hydrogen bonding,resulting in an observed molecular weigh

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If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

Vedclass · Answer

(A) Acetic acid $(CH_3COOH)$ undergoes dimerization in nonpolar solvents like benzene due to hydrogen bonding,resulting in an observed molecular weight that is double the theoretical value.In polar solvents like water,acetic acid undergoes dissociation into ions ($CH_3COO^-$ and $H^+$),resulting in an observed molecular weight that is lower than the theoretical value.Since the extent of association or dissociation depends on the polarity of the solvent,the molecular weight determined by the depression in freezing point method is different in benzene and water.Thus,both the Assertion and Reason are correct,and the Reason correctly explains why the molecular weight differs due to the solvent's polarity.

Assertion : The molecular weight of acetic acid determined by depression in freezing point method in benzene and water was found to be different.
Reason : Water is polar and benzene is nonpolar.

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Assertion : The molecular weight of acetic acid determined by depression in freezing point method in benzene and water was found to be different.Reason : Water is polar and benzene is nonpolar.