Concept:Metamerism is a distinct type of structural isomerism observed in compounds containing polyvalent (multivalent) functional groups, such as ethers, ketones, and secondary amines.
Solution:- Metamers have the exact same functional group and the same total number of carbon atoms.
- They arise purely because the alkyl chains (distribution of carbon atoms) on either side of the polyvalent functional group are different.
- For example, diethyl ether (\( \text{C}_2\text{H}_5\text{-O-C}_2\text{H}_5 \)) and methyl propyl ether (\( \text{CH}_3\text{-O-C}_3\text{H}_7 \)) are metamers.
Why other options are incorrect:Difference in functional group is functional isomerism. Difference in position of the functional group is position isomerism. Shifting of a proton defines tautomerism.
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