Concept:Compounds with the same molecular formula that possess entirely different functional groups exhibit functional group isomerism.
Solution:- The formula \( \text{C}_2\text{H}_6\text{O} \) fits the general formula \( \text{C}_n\text{H}_{2n+2}\text{O} \), which applies to saturated aliphatic alcohols and ethers.
- It can be drawn as ethanol (\( \text{CH}_3\text{CH}_2\text{OH} \)), which is an alcohol.
- It can also be drawn as dimethyl ether (\( \text{CH}_3\text{-O-CH}_3 \)), which is an ether.
- Since the functional group differs, this is functional group isomerism.
Why other options are incorrect:There are not enough carbon atoms to form different chain structures (chain isomerism) or metameric variations (requires at least 4 carbons for ethers). Position isomerism requires the same functional group to move along a larger chain.
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