Chemistry Fundamental Principles of Organic Chemistry ETEA 2022
PMDC Verified Question 43 of 83
The isomers of a substance must have:
A
Same molecular mass
B
Same chemical properties
C
Same structural formula
D
Same functional group
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option A: Same molecular mass
Concept:

Isomers are defined as different compounds that share the exact same molecular formula.

Solution:

  • Because isomers have the exact same molecular formula (same number and types of atoms), they must inherently have the same molecular mass.


  • This is the absolute baseline requirement for any two molecules to be considered isomers.


Why other options are incorrect:

Isomers often have different chemical properties (B), always have different structural formulas or spatial arrangements (C), and functional isomers have different functional groups (D).

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