Introduction

Question 1

What is a homologous series?

Answer 1

A homologous series is a group of organic compounds that have similar chemical properties, due to them having the same functional group.

Question 2

How does fractional distillation work?

Answer 2

• crude oil is heated and vaporized
• The column is hot at the bottom and cool at the top(temperature gradient)
• Vapour rises up through the coloumn and hydrocarbons fractions condense at different heights.
• Shoter hydrocarbons have lower boiling points due to weaker IMFs so condense higher up the column
• Longer hydrocarbons have higher boiling points due to stronger IMFs so condense near the bottom

Question 3

What’s a hydrocarbon?

Answer 3

hydrocarbon is a compound of hydrogen and carbon only

Question 4

Explain what is meant by the term saturated hydrocarbon.

Answer 4

A Saturated hydrocarbon is a hydrocarbon in which all the carbon-carbon bonds are single bonds

Question 5

State the general formula for alkanes.

Answer 5

CnH2n+2

Question 6

State one use of bitumen.

Answer 6

Used to surface roads

Question 7

State two conditions used in catalytic cracking

Answer 7

• Silica
• Alumina

Question 8

Define functional group and isomerism

Answer 8

• Functional group: A group of atoms bonded in a specific arrangement that influences the properties of the homologous series.
• Isomerism: Compounds that have the same molecular formula but different displayed formulae.

Question 9

Explain how to name organic compounds using IUPAC nomenclature.

Answer 9

• The first part of the name indicates the number of carbon atoms:

Meth: 1 carbon atom
Eth: 2 carbon atoms
Prop: 3 carbon atoms
But: 4 carbon atoms
Pent: 5 carbon atoms
Hex: 6 carbon atoms

• The second part of the name indicates the functional group and family of the compound.

Question 10

Classify the following reactions of organic compounds:

Substitution
Addition
Combustion

Answer 10

• Substitution: It’s where one functional group is replaced by another in the presence of UV light.
• Addition: It’s when two or more molecules combine to form larger molecules with no other products.
• Combustion: It’s when an organic substance reacts with oxygen to form carbon dioxide (or carbon monoxide if incomplete combustion) and water.