Given below are two statements:
**Statement I:** The boiling points of aldehydes and ketones are higher than h

Question

Given below are two statements:
**Statement I:** The boiling points of aldehydes and ketones are higher than hydrocarbons of comparable molecular masses because of weak molecular association in aldehydes and ketones due to dipole-dipole interactions.
**Statement II:** The boiling points of aldehydes and ketones are lower than the alcohols of similar molecular masses due to the absence of H-bonding.

In the light of the above statements, choose the most appropriate answer from the options given below:

Accepted Answer

**Statement I is correct:** Aldehydes and ketones contain a polar carbonyl group ($>C=O$), which causes them to undergo weak intermolecular dipole-dipole interactions. These dipole-dipole forces are stronger than the weak van der Waals dispersion forces present in non-polar hydrocarbons, resulting in higher boiling points for aldehydes and ketones of comparable molecular masses.

**Statement II is also correct:** Alcohols contain a highly polar $-OH$ group capable of forming strong intermolecular hydrogen bonds. Because aldehydes and ketones do not have hydrogen atoms directly attached to an electronegative oxygen atom, they cannot form intermolecular hydrogen bonds with themselves. Therefore, their boiling points are lower than those of alcohols of similar molecular masses.

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