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Hydrocarbons

Long Answer Type

211.

What are the characteristics of a compound to be aromatic?
Or
What do you mean by aromaticity?
Or
What are the necessary conditions for any system to be aromatic?

231 Views

212.

Write a short note on annulenes.

184 Views

Short Answer Type

213.

Explain why the following systems are not aromatic?

307 Views

Long Answer Type

214. Give the various methods used for the preparation of arenes.

139 Views

Short Answer Type

215.

How would you convert the following compounds to benzene:
Ethyne

152 Views

216.

How would you convert the following compounds to benzene:
Ethene

133 Views

217.

How would you convert the following compounds to benzene:
Hexane

308 Views

Long Answer Type

218.

How would you convert the following compounds to benzene:
(i) Benzoic acid
(ii) Benzene diazonium chloride?

529 Views

219.
Discuss the halogenation reactions of arenes.

Halogenation: Benzene reacts with chlorine or bromine in the presence of ferric or aluminium halide at room temperature to form substituted product.

Iodination: Reaction of benzene with iodine is not possible because of its reversible nature i.e. HI formed reduces the iodo derivative back to the starting hydrocarbon.

However, the forward reaction is carried out by heating benzene with iodine in the presence of iodic acid (HIO₃) which oxidises HI formed to iodine.

Similarly, toluene also undergoes halogenation under similar conditions giving a mixture of ortho and para disubstituted products.