Organic Chemistry

Question 1

How is crude oil split up into its different fractions?

Answer 1

Fractional distillation

Question 2

Describe how the fractional distillation works

Answer 2

The oil is heated until most of it has turned into gas. The gases enter a fractioning column. Inside the column there’s a temperature column, it’s hot at the bottom and gets cooler as you go up.

Question 3

Why are bottle caps used?

Answer 3

To stop the separated liquids from running back down the column and remixing

Question 4

What are the fractions of crude oil and their uses?

Answer 4

Refinery gases - used for bottled gas
Petrol - fuel for cars
Naphtha - used to make plastics 
Kerosene - jet engines 
Diesel - fuel for trucks 
Fuel oil - fuel for big ships
Bitumen - road surfacing

Question 5

When is carbon monoxide produced?

Answer 5

Incomplete combustion

Question 6

Why is carbon monoxide dangerous?

Answer 6

It is poisonous. It combines with haemoglobin in blood cells, meaning the blood can carry less oxygen

Question 7

When are Sulfur dioxide and nitrogen oxides released?

Answer 7

When fossil fuels are burnt

Question 8

How is acid rain formed ?

Answer 8

When Sulfur dioxide mixes with clouds, forming new dilute Sulfuric acid

Question 9

What is cracking?

Answer 9

When long-chain hydrocarbons are split into more useful short-chain molecules

Question 10

Why is cracking needed?

Answer 10

Because there is a much higher demand for short-chain hydrocarbons than there is for long-chain ones.

Question 11

What kind of reaction is cracking?

Answer 11

Thermal decomposition

Question 12

What are the conditions required for cracking?

Answer 12

Heat plus a catalyst

Question 13

What is a hydrocarbon?

Answer 13

A molecule made up of hydrogen and carbon atoms only

Question 14

What are the names of the first 5 alkanes?

Answer 14

1. Methane
2. Ethane
3. Propane
4. Butane
5. Pentane

Question 15

What is a homologous series?

Answer 15

A group of chemicals that have similar chemical properties, can be represented by a general formula and have the same functional group

Question 16

What is general formula of the alkanes?

Answer 16

CnH2n+2

Question 17

What does saturated mean?

Answer 17

It means only contains carbon-carbon single bonds only

Question 18

What is the equation for complete combustion?

Answer 18

Alkane + oxygen ————> carbon dioxide + water

Question 19

What colour flame burns in complete combustion?

Answer 19

Blue

Question 20

What is the equation for incomplete combustion?

Answer 20

Alkane + oxygen ——> carbon + carbon monoxide +carbon

Dioxide + water

Question 21

What colour flame burns in incomplete combustion?

Answer 21

Smoky yellow flame

Question 22

What is the difference between alkanes and alkenes?

Answer 22

Alkenes have a carbon-carbon double bond, so are unsaturated

Question 23

What is the general formula of the alkenes?

Answer 23

CnH2n

Question 24

Where is ethene produced from?

Answer 24

Crude oil

Question 25

What does ethene react with to form ethanol?

Answer 25

Steam - H20

Question 26

What conditions does ethanol require to be formed? (Temperature, Pressure)

Answer 26

300* | 60-70 atm

Question 27

What is the catalyst that is used?

Answer 27

Phosphoric acid

Question 28

Why is it currently a cheap process?

Answer 28

Ethene is fairly cheap and not much of it is wasted

Question 29

Why will using ethene to make ethanol become expensive in the future?

Answer 29

Crude oil is a non renewable source that will start running out soon

Question 30

What is the other way ethanol is formed ? (In drinks)

Answer 30

Fermentation

Question 31

What is the raw material for fermentation and what is the catalyst?

Answer 31

Sugar - glucose and yeast

Question 32

At what temperature does fermentation occur?

Answer 32

30*

Question 33

What is an advantage of fermentation?

Answer 33

The raw materials are renewable resources

Question 34

What are the disadvantages of fermentation?

Answer 34

The ethanol you get isn't very concentrated so it needs to be distilled to increase its strength. It also needs to be purified

Question 35

How can you turn ethanol into ethene?

Answer 35

Removing the water in a dehydration reaction

Question 36

What is the catalyst when you turn ethanol into ethene?

Answer 36

Aluminium oxide

Question 37

Under what conditions are addition polymers made?

Answer 37

Under high pressure with a catalyst

Question 38

What does condensation polymerisation usually involve?

Answer 38

Two different types of monomer

Question 39

Why are polymers difficult to get rid of?

Answer 39

Because they are inert

Question 40

What does biodegrade mean?

Answer 40

Be broken down by bacteria