Why are boiling points of ethrs lower th...

Why are boiling points of ethrs lower than those of alcohols of comparable molecular masses ?

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The boiling points of ehters are lower than those of alcohols of compareble of comparable molecular masses. For example, the boiling points of isomeric n-bytyl alcohol `(C_(4)H_(9)OH)` and diethyl ether `(C_(2)H_(5)-O-C_(2)H_(5))` are 390 K and 308 K respectively. The large difference in the boiling may be attributed to the following reasons :
(i) O-H bond in alcohol is more polar C-O bond in ether.
(ii) Intermolecular hydrogen bonding is present in the molecules of alcohol while it is almost absent in the ether molecules.

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Assertion: The boiling points of alcohols are higher than those of hydrocarbons of comparable molecular mass. Reason Alcohols show intramolecular hydrogen bonding.

Assertion and reason both are correct statements and reason is correct explanation for assertion.

Assertion and reason both are correct statements but reason is not correct explanation for assertion.

Assertion is correct statement but reason is wrong statement.

Assertion is wrong statement but reason is correct statement.

Carboxylic acids have higher boiling points than aldehydes, ketones and even alcohols of comparable molecular mass. It is due to their :

Formation of intramolecular H-bonding

Formation of carboxylate ion

Formation of intermolecular H-bonding

More extensive association of carboxylic acid via van der Waals force of attraction

Assertion (A) : The weak polarity of ethers does not appreciably affect their boiling points which are comparable to those of alkanes of comparable molecular masses. Reason (R) :Miscibility of ethers with water resembles that of alcohols of the same molecular mass.

Both Assertion (A) and Reason (R) are correct statements, and Reason (R) is the correct explanation of the Assertion (A).

Both Assertion (A) and Reason (R) are correct statements, but Reason (R) is not the correct explanationof the Assertion (A).

Assertion (A) is correct, but Reason (R) is incorrect statement.

Assertion (A) is incorrect, but Reason (R) is correct statement.