Brainscape's Knowledge GenomeTM

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


See full index

Chemistry - Unit 1 > C1 - Crude Oil > Flashcards

C1 - Crude Oil Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

What is a mixture?

A

A mixture consists of multiple elements or compounds that aren’t chemically bonded to each other

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

What are hydrocarbons?

A

Fuels made from carbon and hydrogen

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

How do we separate all of the different hydrocarbons in crude oil?

A

Fractional distillation

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

What is the place where fractional distillation happens called?

A

The fractionating column

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

Describe how fractional distillation works

A

Crude oil is put into the bottom of the column and the bottom is heated

The vapourised oil travels up the column and condenses in fractions of different heights depending on the type of hydrocarbon (the temperature decreases as you go up the column)

Every fraction has an outlet where its type of hydrocarbon can be let out

At the top of the column, the refinery gas is collected (this still hasn’t condensed)

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

List all of the types of hydrocarbons outputted from the column from bottom to top

A

Bitumen (road material)

Oil

Diesel

Kerosene (jet fuel)

Naphtha

Petrol

Refinery gas (bottled gas)

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

What decides where a hydrocarbon will condense?

A

The length of the molecule

The longer the molecule, the higher the temperature when it condenses

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

What are alkanes?

A

Chains of carbon atoms surrounded by hydrogen atoms

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

What are the first 4 alkanes?

A

Methane (natural gas)

Ethane

Propane

Butane

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

What does saturated mean?

A

When all atoms have made bonds with as many other atoms as they can

Only single bonds

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

What is the formula that tells us how many hydrogens or carbons there are in an alkane?

A

The number of carbons is n

The number of hydrogens is 2n+2

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

What are the 3 basic trends of hydrocarbons?

A

The shorter the molecules, the less viscous (less gloopy) it is

The shorter the molecules, the more volatile it is (turn into gas at lower temperature)

The shorter the molecules, the more flammable it is

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

Why is refinery gas suitable for use as bottled gas?

A

Its volatility allows it to be used as a gas at room temperature

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

Why is petrol suitable for car fuel?

A

A liquid can be stored in the engine easily

It is easily vaporised so it can mix with the air before ignition

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

What are very viscous hydrocarbons used for?

A

Lubricating engine parts and covering roads

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

Give 4 advantages of crude oil

A

Burned to make energy and heat for homes

Make chemicals and plastics

Easiest and cheapest to use because things are made to use these fuels

Very reliable

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

What are the 3 disadvantages of crude oil?

A

It is limited and unsustainable

Burning them creates pollution

The ways that we obtain crude oil can scar the landscape

18
Q

What is crude oil?

A

A mixture of different hydrocarbons

19
Q

What are the 2 environmental problems with crude oil?

A

Oil spills can cause damage to animals

Burning it to release energy causes global warming, global dimming and acid rain

20
Q

What is the chemical equation for burning a hydrocarbon?

A

Hydrocarbon + oxygen

–> carbon dioxide + water vapour

21
Q

How does burning hydrocarbons cause acid rain?

A

The sulphur impurities in the oil is released as sulphur dioxide when the fuel is burned

22
Q

When are nitrogen oxides released when burning hydrocarbons?

A

When the combustion is taking place at high temperature

23
Q

What is complete combustion?

A

When there is enough oxygen and all of the fuel is burned

24
Q

What happens when there isn’t enough oxygen and what is this called?

A

When partial combustion happens, solid particles (particulates) of soot (carbon), unburnt fuel and carbon monoxide are released

25
Q

Describe how acid rain is caused

A

Sulphur dioxide is released into the air as a by-product of burning hydrocarbons

Sulphur dioxide mixes with clouds to form sulphuric acid which falks to the ground as acid rain

26
Q

What are the 2 problems with removing the sulphur from fuels before burning them?

A

More expensive

Uses energy causing the release of more carbon dioxide

27
Q

What are the 2 other ways of reducing sulphur emissions?

A

Reduce usage of fossil fuels

Power stations have acid gas scrubbers to take harmful gases out before fumes are released into the atmosphere

28
Q

What is the problem with releasing carbon dioxide into the atmosphere?

A

Causes global warming which causes other types of climate change and risk of flooding due to the polar ice caps melting

29
Q

What is global dimming?

A

The fact that less sunlight has been reaching the surface of the Earth over time

30
Q

What causes global dimming?

A

Particles of soot and ash that are produced when fossil fuels are burned reflect sunlight back into space

31
Q

What are the 3 alternative fuels to hydrocarbons?

A

Ethanol

Biodiesel

Hydrogen gas

32
Q

How is ethanol made and what are the advantages and disadvantages?

A

Made by fermentation of plants

Carbon dioxide released was taken in by the plant as it grew and the only other product is water

Engines need to be converted to work with ethanol and it isn’t widely available

33
Q

How is biodiesel made and what are its advantages and disadvantages?

A

Produced from vegetable oils

Carbon neutral, engines don’t need conversion, produces hardly any sulphur dioxide or particulates

Can’t be made fast enough to replace diesel and it is expensive to make

34
Q

How is hydrogen gas made and what are its advantages and disadvantages?

A

Electrolysis of water

Combines with oxygen in the air to form water

Expensive engine, need energy from another source to make it, hard to store because it’s explosive

35
Q

What is cracking?

A

Splitting up long-chain hydrocarbons into more desirable short-chain hydrocarbons

36
Q

What 2 products do we usually get from cracking?

A

Fuels like petrol and paraffin

Simple hydrocarbons like ethene which is needed for making plastics

37
Q

What does cracking turn diesel into?

A

Petrol, paraffin and ethene

38
Q

What type of reaction does cracking use?

A

Thermal decomposition

39
Q

Describe the procedure of cracking

A

The long-chain hydrocarbon is heated until it is vapourised

The vapour is passed over the powdered catalyst which is aluminium oxide at a temperature of 400 to 700 degrees C

The long-chain molecules split apart on the surface of the specks of aluminium oxide

40
Q

How do branching chains or lined-up chains affect a plastic?

A

Branching chains are softer, easier to melt and lower density

Chemistry - Unit 1 (7 decks)

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