Identify the aromatic compounds among the given set based on Huckel's rule:

Step-by-step solution

According to Huckel's rule, a compound is aromatic if it is cyclic, planar, fully conjugated, and has (4n + 2) electrons, where n = 0, 1, 2, Compound (I): Cyclopropenyl cation is cyclic, planar, and fully conjugated. It has 2 electrons. 4n + 2 = 2 n = 0 . Thus, it is aromatic. Compound (II): Naphthalene is cyclic, planar, and fully conjugated. It has 10 electrons ( 5 double bonds). 4n + 2 = 10 n = 2 . Thus, it is aromatic. Compound (III): Cyclopentadiene contains an sp^3 hybridized carbon atom, which breaks the con