Synthesis- Alkenes

Question 1

How can alkenes be prepared?

Answer 1

• dehydration of alcohols using aluminium oxide, concentrated sulfuric acid or concentrated phosphoric acid
• base-induced elimination of hydrogen halides from
  monohaloalkanes

Question 2

Describe the electrophilic addition reactions alkenes take part in.

Answer 2

• hydrogen to form alkanes in the presence of a catalyst
• halogens to form dihaloalkanes
• hydrogen halides to form monohaloalkanes
• water using an acid catalyst to form alcohols

Question 3

What is Markovnikov’s Rule?

Answer 3

When a hydrogen halide or water is added to an unsymmetrical alkene the hydrogen atom becomes
attached to the carbon with the most hydrogen atoms attached to it already

Question 4

What can Markovnikov’s Rule be used to predict?

Answer 4

Major and minor products formed during the reaction of a hydrogen halide or water with alkenes