Arenes

Question 1

Arenes / Aromatics

Answer 1

HYDROCARBONS with one or more BENZENE rings.

Aromatic is a traditional name as scientists thought benzene rings gave rise to FRAGRANCES (not in practice)

Question 2

SOURCES of benzene

Answer 2

• Fractional distillation of CRUDE OIL ~ condenses at its boiling point (80.1C)
• COAL

Question 3

Aromatic compounds ~ ONE substituent group on the benzene ring

Answer 3

• Alkyl groups ~CH3, CH2CH3, CH2CH2CH3
• Halogens ~ F, Cl, Br, I
• Nitro groups

Question 4

Aromatic compounds ~ MORE THAN ONE substituent group on the benzene ring

Answer 4

• The ring is NUMBERED like a carbon chain, starting at one of the substituent groups
• Listed in ALPHABETICAL order
• Using the LOWEST number possible

Question 5

Identification of an arene

Answer 5

• The number of carbons and hydrogens are ALMOST EQUAL
• There are MORE carbons than hydrogens

Question 6

When is ‘phenyl’ used as a prefix instead of ‘benzene’

Answer 6

Benzene ring attached to either:

• An alkyl chain with a functional group
• An alkyl chain with seven or more carbons