According to Huckel's rule, an integer value of '' must be found for an entirely conjugated planar r — Hydrocarbons Chemistry Question

💡 Solution & Explanation

Naphthalene consists of two fused benzene rings and possesses 5 double bonds, yielding a completely delocalized cloud of 10 $\pi$ electrons. Setting $4n + 2 = 10$ yields $4n = 8 \implies n = 2$. Benzene has 6 $\pi$ electrons ($n=1$). Anthracene and Phenanthrene are three-ring systems containing 14 $\pi$ electrons ($n=3$).