IAL Chemistry-Arenes

Give 3 evidences why delocalised structure of benzene is preferred over Kekule structure.

Answer explanation

1. 1. X-ray Crystallography

2. 2. IR Spectrum

3. 3. Bromine Water Test

4. 4. Enthalpy Change of Hydrogenation

5. 5. Isomerism of Dichlorobenzene

State the type of reaction Kekule structure of benzene can easily undergo but delocalised structure can't easily undergo

Which orbital overlaps in the delocalised structure of benzene, and which type of bond are formed?

• s orbital, σ bond

• p orbital, σ bond

• s orbital, π bond

• p orbital, π bond

What is the real enthalpy change of hydrogenation of benzene in kJ/mol

• -120

• -210

• -280

• -360

Using Q3 above, find the delocalisation energy of benzene in kJ/mol

What is the IUPAC name of this compound

Which catalyst is used in Nitration of Benzene

• Dilute Sulfuric Acid

• Concentrated Sulfuric Acid

• Iron(III) Bromide

• Aluminum Chloride

Describe the mechanism of Friedel-Crafts acylation/alkylation

Answer explanation

Friedel-Crafts acylation/alkylation involves the electrophilic substitution of an aromatic ring with an acyl/alkyl group using a Lewis acid catalyst like AlCl3.

Which conditions and reagents are used for sulfonation reaction of benzene

• Fuming Sulfuric Acid

• Fuming Sulfuric Acid, Reflux

• Concentrated Sulfuric Acid

• Concentrated Sulfuric Acid, Reflux

How to test phenol

• Bromine water

• Bromine

• Bromine water, Heat

• Bromine, Heat