Alkanes

Question 1

What are the products of complete combustion of hydrocarbons?

excess of oxygen

Answer 1

carbon dioxide(CO2)
water (H2O)

Question 2

What are the products of incomplete combustion of hydrocarbons?

limited oxygen

Answer 2

CO2
CO
C
H20

C3H

Question 3

Name the reactions used to make alkanes.

Answer 3

hydrogenation
(addition of hydrogen)
cracking

Question 4

What may be formed as a result of cracking?

Answer 4

Shorter alkanes/H2
and
Alkenes

Alkenes are always formed

Question 5

State the conditions for cracking.

Answer 5

Al2O3
Heat

Al2O3= Alumina

Question 6

State the conditions for the free radical substitution of alkanes.

Answer 6

UV RAYs

Question 7

What are the 3 components of the mechanism for free radical substituition?

Answer 7

• Initiation
• Propagation
• Termination

Question 8

What’s the general equation for combustion of hydrocarbons?

Answer 8

CxHy + (x + y/4)O2 —-> xCO2 + y/2 H20

Question 9

What type of fission is involved in free radical substitution of alkanes?

Answer 9

Homolytic substitution

(formation of free radicals)