Free Radical Substitution

Question 1

Radical

Answer 1

A species that contains an unpaired outershell electron

Question 2

Homolytic Fission

Answer 2

Breaking of a covalent bond where each of the bonding pair of electrons leaves with one species forming a radical

Question 3

Initiation

Answer 3

Formation of radicals, usually as a result of bond breaking caused by UV light

Question 4

Propagation

Answer 4

Two steps that when repeated many times convert the starting materials into products

Question 5

Termination

Answer 5

Formation of a molecule from two radicals

Question 6

Substitution reaction

Answer 6

An atom or group is replaced with another atom or group

Question 7

Explain clearly the steps behind FRS

Answer 7

1. Initiation: -homolytic fission forms two radicals under UV LIGHT
   Cl2➝ 2Cl•
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2. Propagation: The 2Cl• react with methane
   •Cl + CH4 ➝ HCl + •CH3

•CH3 + Cl2 ➝ CH3Cl + •Cl
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3.Termination: Reaction ends by the joining of Two radicals
•CH3 + •Cl ➝ CH3Cl

Question 8

Two reasons why there are many organic products produced during FRS

Answer 8

• Different radicals combine to form different species

* The products can react again to form more compounds