(A) Colligative properties depend on the number of particles in the solution.Benzoic acid $(C_6H_5COOH)$ undergoes dimerisation in non-polar solvents

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(A) Colligative properties depend on the number of particles in the solution.Benzoic acid $(C_6H_5COOH)$ undergoes dimerisation in non-polar solvents like benzene due to hydrogen bonding.This process reduces the total number of particles in the solution.Since the colligative property is inversely proportional to the molar mass,a decrease in the number of particles leads to an abnormally high observed molecular mass compared to the theoretical value.

Class 12 Chemistry Solutions Abnormal molecular mass

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Assertion : Molecular mass of benzoic acid when determined by colligative properties is found high.
Reason : Dimerisation of benzoic acid.

AIIMS 1998 All AIIMS

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If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
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If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
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If the Assertion is correct but Reason is incorrect.
D
If both the Assertion and Reason are incorrect.

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Assertion : Molecular mass of benzoic acid when determined by colligative properties is found high.Reason : Dimerisation of benzoic acid.

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If a solute associates in a solvent, its experimentally calculated molar mass using the boiling point elevation method will be

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Assertion : Molecular mass of benzoic acid when determined by colligative properties is found high.
Reason : Dimerisation of benzoic acid.