Here are the essential concepts you must grasp in order to answer the question correctly.
Resonance Structures
Resonance structures are different Lewis structures for the same molecule that depict the delocalization of electrons within the molecule. They are used to represent molecules where the electron distribution cannot be described by a single Lewis structure. Resonance structures differ only in the positions of electrons, not in the positions of atoms.
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Structural Isomers
Structural isomers are compounds with the same molecular formula but different connectivity of atoms. Unlike resonance structures, structural isomers have different physical and chemical properties because the atoms are connected in different ways, leading to distinct compounds.
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Electron Delocalization
Electron delocalization refers to the spreading of electron density across several atoms, which is a key feature in resonance. This concept helps explain the stability of molecules with conjugated systems, where electrons are shared over multiple bonds, reducing the overall energy of the molecule.
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