18. Aromatic Chem

Question 1

Benzene v Cycolhexa-1,3,5-triene
Model Answer

Answer 1

Bonding:
- each C atoms has 3 cov bonds
- delocalised spare e- in p orbital overlap to form pi cloud
Shape:
- planar, hexagonal, c-c bonds equal in length
Stability:
- expected delata H hydrogenatio of cycla — = -360 kJ mol-1
- delta h hydrogenation of benzene less exothemric by 152 kJ mol-1
- benzene more stable than cycla —