Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

gcse Chemistry > Crude Oil > Flashcards

Crude Oil Flashcards

You may prefer our related Brainscape-certified flashcards:
GCSE Geography - AQA flashcards AP® Chemistry flashcards GCSE Religious Studies - Edexcel Route B flashcards GCSE Religious Studies - Eduqas Route A flashcards GCSE Religious Studies - Edexcel Route A flashcards GCSE Religious Studies - Eduqas Route B flashcards Periodic Table flashcards Chemistry 101 flashcards Organic Chemistry 101 flashcards
1
Q

How is crude oil formed (6 steps)

A

From soft remains of sea plants/ animals on the ocean floor

These remains get buried deeper into the soil

Exposed to intense temperatures and pressures

Chemical changes begin to firm crude oil and natural gas

These substance are less dense than water so pass through permeable rock

Eventually they hit impermeable rock and can’t go any further

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

Why does the oil get forced upwards when drilled

A

Oil and gas are trapped under intense pressures

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

What are hydrocarbons

A

Compounds that are only naked up of hydrogen and carbon atoms

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

What is a fraction

A

Fractions are mixtures of substances of similar size and boiling point

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

How does crude oil get separated into fractions (process + 4 steps)

A

Fractional distillation

Crude oil is heated to become a gas

It enters the bottom of the column where it is hottest

The gases start to rise up the column and cool

The different sized molecules have different boiling points so they condense at different temperatures. So the small molecules with lower boiling points condense at the top and the larger molecules with high boiling points condense at the bottom

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

What is heavy crude oil

A

Contains more long chain hydrocarbons that are dark and viscous

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

What is light crude oil

A

Contains more short chain hydrocarbons which is more runny

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

Why is light crude oil more expensive than heavy crude oil

A

Light crude oil have more useful small hydrocarbons than heavy crude oil

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

Why do short carbon chains have a low boiling point

A

Smaller, lighter molecules have weaker intermolecular forces between them so need less energy to break them

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

Why do short carbon chains burn with a clean flame

A

Smaller molecules are able to burn more easily so it can completely combust

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

Why are short carbon chains runny

A

Smaller molecules can pass over each other easily so

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

Why do long carbon chains have high boiling points

A

Longer, heavier molecules have stronger intermolecular forces so need lots of energy to break them

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

Why do long carbon chains burn with a sooty flame

A

Larger molecules burn less easily so there is incomplete combustion

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

Why are long carbon chains viscous

A

Larger molecules easily become tangled which reduces the runniness of a liquid

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

Why are fossil fuels finite resources

A

They are limited so will eventually run out

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

What does crude oil consist of

A

A mixture of hydrocarbons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the simplest family if hydrocarbons

A

Alkanes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

First 6 alkanes

A 
Methane
Ethane
Propane
Butane 
Pentane
Hexane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the general formula for an alkane

A

C(n)H(2n+2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Are alkanes saturated or unsaturated… What does this mean

A

Saturated - it consists of only single bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are combustion reactions

A

Oxidation reactions - adding oxygen

22
Q

What is complete combustion

A

Occurs when a substance burns with a plentiful supply of oxygen

23
Q

What are the products of complete combustion

A

Carbon dioxide + water

24
Q

General equation for complete combustion

A

Substance + oxygen —> carbon dioxide + water (+ energy)

25
Q

If something needs more oxygen to combust what is it more likely to have when it is burning

A

Black smoke

26
Q

What is incomplete combustion

A

Occurs when a substance burns where oxygen supply is limited or the hydrocarbon chain is long

27
Q

What are the products of incomplete combustion

A

Carbon monoxide, carbon and water

28
Q

What is the general formula for incomplete combustion

A

Substance + oxygen —> carbon (monoxide) + water

29
Q

What is the problem with the gases being produced during incomplete combustion

A

The gas produced which is CO attaches to the haemoglobin in he blood which prevents the transport of oxygen and leads to suffocation

30
Q

Why does sulfur dioxide get produced when burning fossil fuels

A

Fossil fuels contains sulfur , the sulfur reacts with oxygen when burnt

31
Q

Describe sulfur dioxide (4)

A

Acidic
Toxic
Soluble
Colourless

32
Q

When does sulfur dioxide cause and how does this happen

A

Causes acid rain

As the rain falls it passes the sulfur dioxide in the air and react together to form acid rain

33
Q

Harmful effects of acid rain (3)

A

Damages trees
Polluters rivers
Kills animals

34
Q

How can sulfur dioxide be reduced to reduce acid rain

What is this process called

A

Desulfurisation

Removing the sulfur dioxide in the flue gas by lining chimneys with a base so it reacts with CaO

35
Q

How are nitrogen oxides formed

A

Nitrogen and oxygen react together under high temperatures of the engine to form nitrogen oxides that go into the air

36
Q

What does nitrogen oxide cause

A

Acid rain and breathing problems

37
Q

How is carbon dioxide formed

A

During combustion of hydrocarbon fuels

38
Q

How is carbon dioxide harmful to the environment

A

It is a greenhouse gas so it absorbs energy causing global warming

39
Q

Effects of global warming (4)

A

Severe weather events
Flooding
Sea levels rise
Temperatures around the world increase

40
Q

How are particulates formed

A

Incomplete combustion of a fuel, they are unburnt hydrocarbons

41
Q

What do particulates cause

A

Global dimming

42
Q

What is global dimming

A

Unburnt hydrocarbons travel into the atmosphere and reflect back rays of light back into space

43
Q

What are the two main problems of using fossil fuels as an energy source

A

Emit toxic gases when burnt which is bad for environment

Finite resource

44
Q

What are the 3 alternative fuels to fossil fuels

A

Biodiesel
Ethanol
Hydrogen

45
Q

Carbon neutral definition

A

The amount of CO2 released by burning plant material/ biodiesel balance with the amount absorbed during photosynthesis so there is no addition CO2 in the atmosphere

46
Q

Advantages of biodiesel (4)

A

Renewable source (derive from plant material so is biodegradable)

Carbon neutral (less global warming)

Burns cleanly in engines (less sulfur dioxide so less acid rain) (less carbon particulates so less global dimming)

47
Q

Disadvantages for biodiesel (2)

A

Land needs to be used to grow biofuel crops

  • –> vegetation/ habitats destroyed (they absorb CO2)
  • –> instead of growing food (famine, increase food prices)

Produces nitrogen oxides (breathing problems + acid rain)

48
Q

What is biofuel

A

A fuel which is derived from plant material

49
Q

How can ethanol be produced for fuel (2)

A

Fermentation of glucose in plants

Hydration of ethene

50
Q

Why are there not any fuels that are completely carbon neutral

A

Fossil fuels are used to make fertilisers for growing biofuel crops. The CO2 released from this do not balance with CO2 absorbed during photosynthesis as burning biofuels also produces CO2

51
Q

Advantages of hydrogen (2)

A 
Burns cleanly (water)
Produces electrical energy
52
Q

Disadvantages of hydrogen (2)

A

Dangerous (explosive)

Gas (hard to store, high pressure cylinders, need constant supply to run fuel cell)

gcse Chemistry (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions