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Hydrocarbons

Long Answer Type

151.

Discuss the free radical mechanism of addition of HBr to propene.
Or
Give the mechanism of addition of HBr to propylene in the presence of peroxide.

276 Views

152. Write IUPAC names of the products obtained by addition reactions of HBr to hex-1-ene:
(i) in the absence of peroxide and
(ii) in the presence of peroxide.

1449 Views

153.

The addition of HBr to propene yields 2-broniopropane, while in the presence of benzoyl peroxide, the same reaction yields 1-bromopropane. Explain and give mechanism.

410 Views

Short Answer Type

154.

Why peroxide effect is shown only by HBr and not by HCl or HI?
Or
Explain why Kharasch effect is shown by HBr only and not by HCl or HI.

1832 Views

Long Answer Type

155. Discuss the mechanism of formation of halohydrin.

237 Views

156.

How do alkenes react with sulphuric acid? Discuss its mechanism.

370 Views

Short Answer Type

157.

Write a short note on hydroboration oxidation.

247 Views

Long Answer Type

158.
What is ozonolysis? What is its significance?

Ozonolysis: When an alkene reacts with ozone in an inert solvent (ether, CCl₄etc.), an explosive and unstable ozonide is formed. The ozonide undergoes hydrolysis producing carbonyl compounds. These two processes, the addition of O₃and hydrolysis are collectively called ozonolysis.

Significance: Ozonolysis is quite useful to locate the position of the double bond in an unknown alkene. This is done as shown below:

(i) Write the structures of the products (aldehydes or ketones or both) with carbonyl groups facing each other.
(ii) Remove oxygen atoms from carbonyl carbon and connect them by a double bond. For example, suppose the products of ozonolysis are ethanal and propanone.