Aromatic Chemistry Flashcards
How are pie-bonds formed?
The overlap of the unhybridised p orbitals on each carbon atom
Fill in the gap:
Electron density is said to be …. to the p bond
localised
What are arenas?
Unsaturated compounds in cyclic shape
What many natural occurring fragrant substance contain?
Substituted benzene rings
What is the molecular formula of a benzene ring?
C6H6
Fill in the gap:
Benzene has … pie-bonds
adjacent
What is meant by Benzene having adjacent p-bonds?
More than two p-orbitals combine to give a set of molecular orbitals in which the electron pairs are shared by more than two atoms
What a delocalised pie-bonds?
Each pie electron is shared by all carbons
What bond length should we expect from c-c?
1.54 A
What bond length should we expected from c=c?
1.33 A
What is the bond length in benzene?
1.40A
What can we deduce from the bond length in benzene of the expected and observed
The electrons are not localised to three p-bonds but are delocalised
Interconversion occurs by movement of pie bonds
What are conjugated molecules?
Altering single and double bonds (sometimes triple bonds)
When do conjugation occur?
When unhybridized p-orbitals on three or more adjacent atoms overlap
What do altering double bonds allow?
Delocalisation of pie bonds
