C9: Crude oil and fuels Flashcards

1
Q

What is a hydrocarbon?

A

A compound containing hydrogen and carbon atoms only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are some uses for crude oil?

A

Plastics
Petroleum
Medicines
Cosmetics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Is crude oil finite or infinite?

A

Finite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Where is crude oil found

A

Formed over millions of years from the remains of tiny sea creatures (namely plankton) that were buried in the mud.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is crude oil?

A

A mixture of hydrocarbons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the general formula for alkanes?

A

CnH2n+2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are alkanes?

A

Saturated hydrocarbons
- contain maximum possible number of hydrogen atoms, containing only single covalent bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the key properties of hydrocarbons?

A

Viscosity - how runny a liquid is
Volatility - how quickly a hydrocarbon reacts
Flammability - how easily a hydrocarbon combusts
Boiling point - how easily a hydrocarbon changes state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How does viscosity vary among hydrocarbons?

A

As chains get longer, viscosity increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How does volatility vary with hydrocarbons?

A

As chains get longer, volatility decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How does flammability vary with hydrocarbons?

A

As chains get longer, flammability decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How does boiling point vary with hydrocarbons?

A

As chains get longer, boiling point increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are some vehicles which run on hydrocarbon fuels?

A

Ships
Planes
Cars

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What happens during general combustion of hydrocarbons?

A

Carbon and hydrogen atoms react with oxygen to become oxidised

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is complete combustion?

A

A hydrocarbon reacting in plentiful oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the equation for the complete combustion of hydrocarbons?

A

Alkane + Oxygen → Carbon dioxide + Water
e.g.
CH4 + 2O2 → CO2 + 2H2O

17
Q

What is the equation for incomplete combustion of hydrocarbons?

A

Alkane + Oxygen → Carbon/ Carbon monoxide + Water
e.g.
CH4 + 2O → C + 2H2O
CH4 + 3O → CO + 2H2O

18
Q

Why must the hydrocarbons in crude oil be separated?

A

In order to obtain useful products

19
Q

How are hydrocarbons separated from crude oil?

A

Fractional distillation, it is separated into fractions, containing hydrocarbons of similar structure

20
Q

Describe the process of fractional distillation

A

Crude oil is heated to high temperatures, until it is vaporised. It is the pumped into the fractionating column, which is hot at the bottom, and cooler at the top. The heaviest, unevaporated hydrocarbons are drained off of the bottom. The vapour the rises up the column, hydrocarbons will condense at different points within the column, upon reaching their boiling point. They are then drained out of the column

21
Q

What is the pattern of hydrocarbons condensing in the fractionating column?

A

Long chains condense towards the bottom, short chains condense towards the top

22
Q

What are fractions?

A

Containing a similar number of hydrocarbon atoms

23
Q

What are some fractions used for and give examples?

A

Fuels - petrol and diesel, kerosene, heavy fuel oil, liquified petroleum gas
Feedstock - solvents, lubricants, detergents, polymers

24
Q

What is the petrochemical industry?

A

Industries which use organic products for manufacture

25
Q

What is feedstock?

A

A chemical that’s used in another chemical

26
Q

Why don’t long-chain hydrocarbons make good fuels?

A

They are not very flammable

27
Q

What is cracking?

A

Converting a long chain hydrocarbon to a small chain hydrocarbon

28
Q

What are the products of cracking?

A

Shorter chain alkane and an alkane (usually ethene)

29
Q

What are the two methods of carrying out cracking?

A

Catalytic cracking
Steam cracking

30
Q

What is catalytic cracking?

A

Using high temperatures (550C) and a catalyst (zeolite -to speed up the reaction)

31
Q

What is steam cracking?

A

Using higher temperatures (800C) and steam

32
Q

What is a homologous series?

A

A family of organic compounds that have the same functional group and similar chemical properties

33
Q

What is the general formula for alkenes?

A

CnH2n

34
Q

What are alkenes?

A

Unsaturated hydrocarbons
- do not contain the maximum number of hydrocarbons and have at least one double carbon bond

35
Q

What is a functional group?

A

The section of (hydrocarbons) which reacts

36
Q

What are alkenes used for?

A

Feedstock

37
Q

What is the reactivity of alkenes as compared to alkanes?

A

Alkenes are more reactive because they have a functional group (are unsaturated)

38
Q

What are some pollutants produced when fuels burn?

A

Sulfur dioxide - acid rain
Particulates - global dimming
Carbon dioxide - global warming