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Flashcards in Organic Chemistry Deck (40):
1

How is crude oil split up into its different fractions?

Fractional distillation

2

Describe how the fractional distillation works

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.

3

Why are bottle caps used?

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

4

What are the fractions of crude oil and their uses?

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

5

When is carbon monoxide produced?

Incomplete combustion

6

Why is carbon monoxide dangerous?

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

7

When are Sulfur dioxide and nitrogen oxides released?

When fossil fuels are burnt

8

How is acid rain formed ?

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

9

What is cracking?

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

10

Why is cracking needed?

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

11

What kind of reaction is cracking?

Thermal decomposition

12

What are the conditions required for cracking?

Heat plus a catalyst

13

What is a hydrocarbon?

A molecule made up of hydrogen and carbon atoms only

14

What are the names of the first 5 alkanes?

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

15

What is a homologous series?

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

16

What is general formula of the alkanes?

CnH2n+2

17

What does saturated mean?

It means only contains carbon-carbon single bonds only

18

What is the equation for complete combustion?

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

19

What colour flame burns in complete combustion?

Blue

20

What is the equation for incomplete combustion?

Alkane + oxygen ——> carbon + carbon monoxide +carbon
Dioxide + water

21

What colour flame burns in incomplete combustion?

Smoky yellow flame

22

What is the difference between alkanes and alkenes?

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

23

What is the general formula of the alkenes?

CnH2n

24

Where is ethene produced from?

Crude oil

25

What does ethene react with to form ethanol?

Steam - H20

26

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

300*
60-70 atm

27

What is the catalyst that is used?

Phosphoric acid

28

Why is it currently a cheap process?

Ethene is fairly cheap and not much of it is wasted

29

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

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

30

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

Fermentation

31

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

Sugar - glucose and yeast

32

At what temperature does fermentation occur?

30*

33

What is an advantage of fermentation?

The raw materials are renewable resources

34

What are the disadvantages of fermentation?

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

35

How can you turn ethanol into ethene?

Removing the water in a dehydration reaction

36

What is the catalyst when you turn ethanol into ethene?

Aluminium oxide

37

Under what conditions are addition polymers made?

Under high pressure with a catalyst

38

What does condensation polymerisation usually involve?

Two different types of monomer

39

Why are polymers difficult to get rid of?

Because they are inert

40

What does biodegrade mean?

Be broken down by bacteria