Consider the molecule $C_6{H}_6$ (benzene). Is this molecule aromatic?

• A. No, because it is not planar.
• B. No, because it has $8$ $\pi$ electrons.
• C. No, because it does not have a continuous ring of p orbitals.
• D. Yes, because it is planar, fully conjugated, and follows Hückel's rule with $6$ $\pi$ electrons.

Answer: (D)

Verified step by step guidance

1. Identify the structure of benzene (C\_6H\_6) as a six-membered carbon ring with alternating double bonds, which suggests conjugation.
2. Check if the molecule is planar, since planarity allows for effective overlap of p orbitals necessary for aromaticity.
3. Verify that the molecule has a continuous ring of p orbitals, meaning each carbon atom must have an unhybridized p orbital overlapping with neighbors to form a conjugated system.
4. Count the number of \pi electrons in the ring. Each double bond contributes 2 \pi electrons, so benzene has 3 double bonds × 2 = 6 \pi electrons.
5. Apply Hückel's rule, which states that a planar, cyclic, fully conjugated molecule is aromatic if it contains (4n + 2) \pi electrons, where n is a non-negative integer. For benzene, 6 \pi electrons fit this rule with n = 1, confirming aromaticity.