Crude oil - making, problems and uses Flashcards Preview

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Flashcards in Crude oil - making, problems and uses Deck (38)
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1
Q

How is crude oil formed?

How is it extracted?

A

The buried remains of plants and animals turns into this over millions of years
Drilling and pumping

2
Q

Crude oil is a mixture
What is a mixture?
What is crude oil a mixture of?

A

Something that contains two or more elements or compounds that aren’t chemically bonded to each other
Different compounds, mostly hydrocarbon molecules

3
Q

How can crude oil be separated out into its different compounds?

A

Physical methods - fractional distillation

4
Q

What does each fraction contain?

A

Molecules with similar numbers of carbon atoms

5
Q

How does the fractional distillation process work? (3)

A

(Working continuously) - the crude oil is heated and piped into the bottom of the column
The vapourised fuel rises up the column
The fractions are tapped off where they condense

6
Q

What is the order and the names of the fractions produced? Start from the bottom (7)
The length of the molecules gets ….. as you go up the column.

A
Bitumen - for roads
Oil - for joints etc
Diesel  -  lorries
Kerosene - jet fuel
Naptha - chemicals
Petrol - cars
Refinery gas, bottle gas - for homes etc burning 
Shorter
7
Q

All the fractions of crude oil are …..

A

hydrocarbons called alkanes

8
Q

What are alkanes?

A

Chains of carbon atoms, surrounded by hydrogen atoms on every bond a carbon has spare (4)

9
Q

What are the first 4 alkanes?

What is their formula?

A

Methane CH4
Ethane C2H6
Propane C3H8
Butane C4H10

10
Q

The carbons form ….. bonds and hydrogen forms …. bond in an alkane.
This is called being …..
What is the alkane general formula?

A

4, 1
saturated
Cn H2n+2

11
Q

The shorter the hydrocarbon molecules the: (3)

A

more runny it is and less viscous
more volatile it is: turn into a gas at a lower temperature , so lower boiling point
more flammable it is

12
Q

What is refinery gas’s useful property?
Why does it have the lowest boiling point?
How is it stored, under what in what?
What happens when it is used with a burner?

A

It is so volatile it is a gas at room temperature
because it has the shortest hydro c chains
Under pressure as liquid in bottles, bottled gas
The cap is removed, it vaporizes and flows into the burner where it’s ignited.

13
Q

The petrol fraction has longer molecules so it has a …
Petrol is in the state of a …. which is ideal for…
What happens to it when it is used in a car?

A

higher boiling point
liquid
storing in cars
It flows into the engine where it is easily vapourised to mix with the air before it’s ignited

14
Q

What does viscous mean?

How this this decide how different fractions are used?

A

having a thick, sticky consistency between solid and liquid

Really gloopy HCarbons are used for lubricating engine parts or covering roads.

15
Q

Why do crude oil fractions make good fuels?

Where are the fractions used? (3)

A

They burn cleanly

In transport and central heating systems/power stations to generate electricity

16
Q

What does the industry surrounding crude oil look at?

A

Where there are more oil reserves to take out of the ground to turn into useful products.

17
Q

What is crude oil used for in the consumer industry?

A

It is the raw materials for making plastics and chemicals

18
Q

What are alternatives to crude oil power?
But what is one problem?
What is the problem with the alternatives? (2)

A

Nuclear, wind, solar etc
Machines and infrastructure is set up for fossil fuels - its easier and cheaper
They aren’t reliable or they create harmful expensive waste

19
Q

Why will crude oil run out? Scientists predict it will run out soon (25 years ish)
Why might it run out later than expected? (2)

A

It’s a non-renewable resource
New reserves are discovered as technology develops and it’s now possible to extract what was previously inaccessible or too expensive.

20
Q

What do some people think we should stop using crude oil for? Why?
And use for just …. and …. instead because?

A

Fuel because there are alternatives

chemicals and medicine, crude oil is essential for these

21
Q

What do we need to do to prepare for new fuels?

A

Develop fuels that release enough energy for everything

Adapt for them

22
Q

When do oil spills happen?

What happens to the environment after an oil spill? (2)

A

When oil is being transported by a tanker in the sea
Birds get covered and are poisoned as they try to clean themselves
Sea otters and whales get poisoned too

23
Q

What is the worst effect of burning crude oil?

A

It is a major cause of global warming, acid rain and global dimming

24
Q

What are the two main things that burn fossil fuels?

A

Cars and power stations for electricity

25
Q

What is the equation for combustion?

A

Hydrocarbon + oxygen = CO2 + Water vapour

26
Q

What happens when the burnt fuel contains sulphur impurities?

A

The sulphur will be released as sulphur dioxide when the fuel is burnt

27
Q

What will be formed if the fuel in a car is burnt at high temps?

A

Nitrogen oxides

28
Q

What happens when there isn’t enough oxygen when burning the fuel?
What is released? (3)

A

Incomplete combustion

Carbon monoxide and solid particles of soot (carbon) and unburnt fuel.

29
Q

What causes acid rain?

How?

A

Sulphur dioxide, nitrogen oxides

It mixes with clouds to form dilute sulphuric acid - falling as acid rain (or dilute nitric acid)

30
Q

What does acid rain cause?
What does it do to infrastructure?
So what needs to be balanced and how is this done?

A

Lakes to become acidic and many plants and animals die as a result
It kills trees and damages limestone buildings and ruins stone statues
The benefits of electricity and travel vs. the environemntal impacts - so international agreements have set targets for reducing emissions of air pollutants such as sulphur dioxide

31
Q

What are the two problems with removing sulphur before the fuel is burnt?
Yet what is happening?

A

It costs a lot of money
It requires further burning of fossil fuels for the energy to remove the impurities
Petrol and diesel are starting to be replaced by low sulphur versions

32
Q

What do power stations have to reduce their sulphur dioxide emissions?
How else can the emissions be reduced?

A

Acid Gas Scrubbers which take out the harmful gases before they’re released into the atmosphere.
Use fewer fossil fuels

33
Q

As the population increases more:

The extra CO2 is:

A

fossil fuels are being burnt so CO2 levels are increasing

causing the average temp of the planet to increase: global warming

34
Q

What is global warming? (2 definitions)

A

A gradual increase in the overall temperature of the earth’s atmosphere due to the greenhouse effect caused by increased levels of carbon dioxide and pollutants
A type of climate change and causes other types of climate change such as changing rainfall patterns, severe flooding and the melting of the ice caps

35
Q

What are the findings for global dimming?

What causes global dimming?

A

Scientists have found that in some areas 25% less sunlight has been reaching the surface since 50 years ago.
Particles of soot and ash produced when FF are burnt reflect the sunlight back into space or help to produce more clouds that do this too.

36
Q

What is ethanol? (How is it produced)
What is it used for?
Pros (2)
Cons (3)

A

From plant material so it’s a biofuel. It’s made by the fermentation of plants. Often mixed with petrol to make it a better fuel
To power cars in some places
The CO2 it releases was absorbed by the plant that made it so it’s carbon neutral. The only other product is water which isn’t a pollutant
Cars’ engines and infrastructure have to be converted to work with ethanol fuels
It isn’t widely available
As demand increases farmers switch from growing food to fuel and s food prices increase

37
Q

What is biodiesel? (How is it produced)
What is it used for?
Pros (3)
Cons (3)

A

A biofuel produced from vegetable oils such as rapeseed or soybean oil . Can be mixed with ordinary diesel and used to run a diesel engine
Carbon neutral, Engines don’t need to be converted, It produces less sulphur dioxide and particulates than petrol or diesel.
Not enough can be made to fully replace diesel, it’s expensive to make, increases food prices

38
Q

How is hydrogen gas produced? why is this bad?
What is it used for?
Pros (1)
Cons (3)

A

Electrolysis of water - requires electricity to split
It combines with oxygen to form water - very clean
You need a special expensive engine
Hydrogen isn’t widely available
You need energy from another source to make it
Hydrogen is hard to store because it’s explosive