MCQ Detailed View

Ethers are organic compounds that have the general formula R–O–R′, where two alkyl or aryl groups are connected by an oxygen atom. Alcohols, on the other hand, have the general formula R–OH, where a hydroxyl group is attached to a carbon atom. Ethers and alcohols are examples of functional group isomers, which means they have the same molecular formula but different functional groups and different structures.

For example, consider the molecular formula C₂H₆O. This formula can represent ethanol (CH₃CH₂OH), which is an alcohol, or dimethyl ether (CH₃OCH₃), which is an ether. Both compounds contain the same number of carbon, hydrogen, and oxygen atoms, but their functional groups are different. Ethanol contains the hydroxyl group (-OH), while dimethyl ether contains an oxygen atom linking two methyl groups.

This difference in functional groups leads to very different physical and chemical properties. Alcohols usually show hydrogen bonding, giving them higher boiling points and greater solubility in water compared to ethers of the same molecular mass. Ethers, due to the absence of hydrogen bonding with themselves, have lower boiling points and are less soluble in water.

Looking at the options:

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  Aldehydes and Ketones are carbonyl compounds and do not have the same molecular formula as ethers.

  
  


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  Carboxylic acids contain the –COOH group and are not isomeric with ethers.

  
  


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  Only Alcohols share the same molecular formula as ethers and differ only in the functional group.

  
  

Therefore, ethers exhibit functional group isomerism with alcohols. This is a common example taught in organic chemistry to illustrate the concept of isomerism.