Arrange the following compounds in decreasing order of their total resonance energy: (I) (II) (III)

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The given compounds are: (I) Naphthalene (II) Benzene (III) Anthracene The total resonance energy of aromatic compounds generally increases with an increase in the number of fused rings due to a larger number of delocalized electrons over a more extended system. The approximate experimental values of total resonance energy for these compounds are: Benzene (II): 36 kcal/mol Naphthalene (I): 61 kcal/mol Anthracene (III): 83 kcal/mol Therefore, the decreasing order of total resonance energy is (III) > (I) > (II). Answ