(Equations and resonance structures for benzene delocalization are present but the main problem text is missing from the excerpts)

Question

(Equations and resonance structures for benzene  delocalization are present but the main problem text is missing from the  excerpts)

Accepted Answer

2.1: 3 C2H2 = C6H6 2.2: (K1) 2.3:  2.4: Eπ = 2t 2.5: EK1 = 3 × 2t = 6t 2.6: (K2) 2.7: EK2 = EK1 = 6t 2.8:  2.9: Using c1^2 + c2^2 = 1, 2.10: EK(H12 = 0) = (1 − c1^2) EK2 + c1^2 EK1 ΔE1 = 7t – 6t = t 2.11: t < 0, so ΔE1 < 0: electronic delocalization contributes to stabilize the benzene molecule. 2.12: See answer 2.13. 2.13:  2.14: EMO = 2 × 2t + 4t = 8t and ΔE2 = (2 × 2t + 4t) – 6t = 2t 2.15: Since t < 0, ΔE2 = 2t < t = ΔE1 2.16: Correct answer: ІΔrHbІ < 3 ІΔrHc°І

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