Alkanes 4.1.2

Question 1

What shape is the bonds around a Carbon in an Alkane?

Answer 1

Tetrahedral

109.5°

Question 2

What is the word equation for the complete combustion of an Alkane?

Answer 2

Alkane + Oxygen → Carbon Dioxide + Water
eg.
C2H4 + 3(O2) → 2(CO2) + 2(H2O)

Question 3

What is the word equation for the incomplete combustion of an Alkane?

Answer 3

Alkane + Oxygen → Carbon Monoxide + Water
eg.
C2H4 + 2(O2) → 2(CO) + 2(H2O)

Question 4

What is the Cracking of a Hydrocarbon?

Answer 4

When a Long chain hydrocarbon is broken in to a short Alkane and a short Alkene

Question 5

Why do Branchless Hydrocarbons have a higher boiling point?

Answer 5

There is greater contact area between the branchless molecules.
Therefore greater induced dipoles

Question 6

What is Free Radical Substitution?

Answer 6

When one or more atoms within a molecule is substituted as a result of interacting witha free radical

Question 7

What is a Free Radical?

Answer 7

Atom or Molecule with an unpaired electron

Question 8

What are the three stages of a Free Radical Substitution?

Answer 8

Initiation:
Radicals are created
Propagation:
Radicals ar eused and regenerated
Termination:
Radicals are removed

Question 9

What is Homolytic Fission?

Answer 9

When a bond is broken between two molecules and both retain one of the bonding electrons

Question 10

What is an example of Initiation?

Answer 10

Cl2 → 2Cl*

Question 11

What are examples of Propagation?

Answer 11

Cl* + CH4 → CH3* + HCl

Cl2 + CH3* → CH3Cl + Cl*

Question 12

What are examples of Termination?

Answer 12

Cl* + Cl* → Cl2
Cl* + CH3* → CH3Cl
CH3* + CH3* →C2H6