PMDC Verified Question 65 of 83
\( \text{C}_4\text{H}_{11}\text{N} \) gives the type of isomerism:
A
Metamerism
B
Optical isomerism
C
Tautomerism
D
None of the above
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option A: Metamerism
Concept:

Metamerism occurs when isomers have the same molecular formula but differ in the distribution of alkyl groups on either side of a polyvalent functional group (like an amine, ether, or ketone).

Solution:

  • The formula \( \text{C}_4\text{H}_{11}\text{N} \) represents a saturated amine.


  • Secondary amines (\( \text{R--NH--R'} \)) are polyvalent.


  • Possible structures include:
    • Diethylamine: \( \text{CH}_3\text{CH}_2\text{--NH--CH}_2\text{CH}_3 \)
    • Methylpropylamine: \( \text{CH}_3\text{--NH--CH}_2\text{CH}_2\text{CH}_3 \)


  • Since the alkyl groups around the central \( \text{-NH-} \) change, it exhibits metamerism.


Why other options are incorrect:

While it can show structural chain isomerism, among the given choices, metamerism is the distinct and most characteristic isomerism for polyvalent functional groups like amines.

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