17.3.1 Benzene and Its Derivatives

• Benzene is an organic compound with the chemical formula C_{6}H_{6}
• All six carbon atoms in benzene lie in the same plane.
• What type of reactions is benzene resistant to due to its stability?

  Addition
• Each carbon atom in benzene is bonded to one hydrogen atom.
• The delocalized electrons in benzene create a stable electron cloud above and below the plane
• Why is benzene highly stable compared to regular alkenes?

  Delocalization of electrons
• Kekulé's structure of benzene includes alternating single and double bonds.
• Kekulé's structure fails to explain why all C-C bond lengths in benzene are equally identical
• What type of reactions does Kekulé's structure incorrectly suggest benzene should undergo easily?

  Addition
• What does delocalization of electrons in benzene create?

  Stable electron cloud
• The delocalization of electrons in benzene contributes to its resistance to addition reactions.
• Benzene is an aromatic hydrocarbon with the chemical formula C6H6
• What is the arrangement of the carbon atoms in benzene?

  Cyclic six-carbon ring
• All carbon atoms in benzene lie in the same plane
• The delocalized electrons in benzene create an electron cloud above and below the plane of the ring.
• What property of benzene is enhanced by the delocalization of electrons?

  High stability
• Kekulé's structure depicts benzene as a six-membered ring with alternating single and double bonds
• What is one limitation of Kekulé's structure regarding bond lengths in benzene?

  Unequal bond lengths
• Experimental data shows all C-C bond lengths in benzene are equal, contradicting Kekulé's structure.
• Kekulé's structure suggests benzene should react like a regular alkene
• What year did Kekulé propose his structure for benzene?

  1865
• Electron delocalization in benzene reduces electron density and minimizes repulsion.
• Delocalization in benzene contributes to its stability through resonance
• Benzene's stability is enhanced by its delocalized electrons.
• What contributes to benzene's stability and resistance to addition reactions?

  Delocalized electrons
• Benzene's delocalized electrons create a stable electron cloud above and below the plane
• Benzene's delocalized electrons are evenly distributed around the ring.
• What is the bond length of a C=C double bond in Kekulé's structure of benzene?

  1.34 Å
• The actual benzene structure has equal C-C bond lengths due to delocalization
• Kekulé's model correctly predicts that benzene has alternating single and double bonds.

  False
• What do the resonance structures of benzene represent?

  Delocalized electron arrangements
• The resonance hybrid of benzene results in uniform C-C bond lengths and enhanced stability
• What is the chemical formula of benzene?

  $C_{6}H_{6}$
• Benzene has a planar structure with all six carbon atoms in the same plane.
• Benzene is a cyclic aromatic hydrocarbon with a planar six-carbon ring
• What creates the stable electron cloud above and below the benzene plane?

  Delocalized electrons
• Match the feature of benzene with its description:

  Planar Structure ↔️ All carbon atoms lie in the same plane

  Delocalized Electrons ↔️ Create a stable electron cloud

  High Stability ↔️ Resistant to addition reactions
• What is the chemical formula of benzene?

  $C_{6}H_{6}$
• Electrons in benzene are evenly distributed around the ring, creating a stable electron cloud
• What contributes to the high stability of benzene?

  Delocalized electrons