Note that your final mark will not be saved in the system.
6.1.1 Aromatic compounds GapFill
You must fill all the gaps before clicking ‘Check Answers!’
Benzene has the molecular formula . Its molecules are flat, hexagonal rings, which the discarded Kekulé model suggested contained alternating double and single bonds. However, it is now known that each carbon atom contributes one electron from a orbital to form a cloud of electrons above and below the ring. This cloud is sometimes called a -system. The enthalpy of of benzene is less exothermic than would be expected for three separate double bonds, implying that this type of bonding makes it more stable. Molecules that experience this stabilisation are said to be ' ', while those that contain at least one benzene ring are called .
Benzene typically undergoes electrophilic substitution reactions, such as nitration, halogenation and Friedel−Crafts reactions. The products of the latter reaction can be alkylbenzenes or , depending on the reactants used.
Benzene rings in which one of the hydrogen atoms has been replaced by an OH group are called .