Given below are two statements:Statement (I): The boiling points of alcohols and phenols increase with increase in the number of C-atoms. Statement (II): The boiling points of alcohols and phenols are higher in comparison to other classes of compounds such as ethers and haloalkanes.
In the light of the above statements, choose the correct answer from the options given below:
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The boiling points of compounds with hydrogen bonding, such as alcohols and phenols, are generally higher compared to compounds like ethers and haloalkanes, which lack hydrogen bonding.
To evaluate the truthfulness of each assertion, let's examine them individually:
Assertion (I): The boiling points of alcohols and phenols rise as the number of C-atoms increases.
Alcohols and phenols both contain hydroxyl groups (\(-OH\)).
The boiling point of these substances is primarily affected by two factors:
Hydrogen bonding: The hydroxyl group enables hydrogen bond formation, significantly elevating boiling points.
Molecular weight: An increase in carbon atoms corresponds to an increase in molecular weight, resulting in higher boiling points due to enhanced van der Waals forces (London Dispersion Forces).
Consequently, the assertion that boiling points increase with more carbon atoms is accurate.
Assertion (II): The boiling points of alcohols and phenols are elevated compared to other compound classes like ethers and haloalkanes.
This elevation is chiefly attributable to hydrogen bonding, which is considerably stronger than the van der Waals forces present in ethers and haloalkanes.
Ethers and haloalkanes exhibit weaker intermolecular forces due to the absence of the hydrogen bonding found in alcohols and phenols.
Thus, alcohols and phenols generally possess higher boiling points than ethers and haloalkanes of similar molecular weight.
Based on the preceding analysis, it can be concluded that both Assertion (I) and Assertion (II) are factual. Accordingly, the correct response is:
