Unit 3 Section 2: Alkanes And Halogenoalkanes

Question 1

What are the conditions for thermal cracking?

Answer 1

High temperature (up to 1000°C) and high pressure (up to 70atm).

Question 2

What are the conditions for catalytic cracking?

Answer 2

A zeolite catalyst, slight pressure and high temperature (about 500°C)

Question 3

What are the products of thermal cracking?

Answer 3

A lot of alkenes; used to make polymers and other valuable products. Poly(ethene) is an example

Question 4

What are the products of catalytic cracking?

Answer 4

Aromatic hydrocarbons and the aliases needed to produce motor fuels

Question 5

Write equations for the mechanism for the reaction of fluorine with fluoromethane (CH3F) to form difluoromethane (CH2F2)

Answer 5

Initiation
F2 -> 2F•
First propagation
F• + CH3F -> •CH2F + HF
Second propagation
F2 + •CH2F -> CH2F2 + F•
Termination
2 •CH2F -> CH2FCH2F