Final answer:
Benzene's electron deficiency is explained by the delocalization of electrons within the ring structure, where six carbon atoms form a hexagon each bonded to a hydrogen atom, and the electrons are shared equally, depicted by a central circle.
Step-by-step explanation:
The electron deficiency in benzene, C6H6, where AE (available electrons) equals 30 and NE (needed electrons) equals 38, is accounted for by the delocalization of electrons within the molecule's structure. Benzene has a unique bonding structure with a six-carbon hexagonal ring that is depicted as a circle in the center of the hexagon to indicate delocalized electrons shared equally by all six carbon atoms.
Each corner of the hexagon is occupied by a carbon atom with one hydrogen atom attached to it, resulting in a stable planar molecule through sp² hybridization of the carbon atoms.
The concept of resonance structures illustrates the delocalization of electrons in benzene which contributes to its stability and is represented by alternating double and single bonds between the carbon atoms in different drawings but understood as a circle in modern representations.