aliphatic :
aromatic or arene: .
aliphatic : straight or branched chain organic substances
aromatic or arene: includes one or more ring of six carbon
atoms with delocalised bonding.
Benzene’s Structure
C6H6
six C atoms in a hexagonal ring, with H atom bonded to each
single covalent σ-bonds.
one unused electron on each C atom in a p orbital, perpendicular to the plane of the ring.
delocalised in a ring structure above and below the plane of carbon atoms
kekule proposition
Kekule suggested the following
structure for Benzene consisting of
alternate single and double covalent
bonds between the carbon atoms