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STRUCTURE OF BENZENE
• In 1825, Michael Faraday
isolated benzene from the oily residue
left by illuminating gas in London street lamps. Further investigation
showed that the molecular formula of this compound was C6H6: a
hydrocarbon comprised of six carbon atoms and six hydrogen atoms.
• 1865 – August Kekulé proposes a cyclic structure for benzene with
alternating single and double bonds.
2025-026 Dr. Marwa El-Wakil 3
Source of Benzene
1. When coal is heated to about 1000ºC in the absence of
oxygen, a mixture of compounds, called coal tar, is released.
Distillation of coal tar yields many aromatic compounds.
2.
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