2. Crude Oil and its Products
Understand: Keywords:
1. How crude oil and other fossil fuels rich in Crude Oil, Formation, Fossil, Fuel,
carbon were formed. Hydrocarbons, Hydrogen, Carbon, Fractional,
2. That crude oil is a mixture of hydrocarbons. Distillation, Alkanes, Alkenes, Cracking,
3. That hydrocarbons contain only two elements: Ethene, Polymers, Plastics, Polymerisation,
hydrogen and carbon.
Greenhouse, Global, Warming & Pollution.
4. That different hydrocarbons have different uses
and can be separated using fractional
distillation.
5. That the alkane family of hydrocarbons are used
mainly as fuels by transport vehicles.
6. The chemical properties of the alkanes and the
alkenes.
7. The use of ethene and other alkenes in the
formation of polymers and plastics.
8. The benefits and costs of using crude oil as
fuels and as a starting material for the
manufacture of plastics.
9. That the increases emissions of carbon dioxide
in the atmosphere is causing the greenhouse
effect.
10. The likely impact of the greenhouse effect.
11. That there are many renewable alternative to
using crude oil as an energy source.
3. Science Interactive LTD Copyright 2005
Oil and natural gas reserves
Underneath the bedrock of some countries of the World like Saudi Arabia, Iraq and Russia are
billions of barrels of c_______ oil. When extracted using drilling rigs, it can be used as a fuel,
and a raw material to manufacture plastics, paints and medicines. The biggest users of crude
oil are the United States followed by Europeans. The country with the greatest reserves of
crude oil is Saudi Arabia, who until the discovery of oil had a simple economy and little
modern infrastructure. Look at the map and find other countries with large reserves ?
World reserves of crude oil: Word bank: crude
World oil reserves Energy use in the modern World
Diagram
Notes World oil reserves are finite. It estimated that This composite picture of the world at night shows us
we currently have around 60 – 80 years of the biggest energy users. North America, followed by
crude oil remaining. Saudi Arabia, Iraq and Europe and Japan are the largest users or energy. These
Russia have the largest reserves with over 50 countries depend most on the ‘cheap energy’ that crude
billions barrels of crude oil underground. oil provides us.
4. Science Interactive LTD Copyright 2005
Formation of crude oil
The formation of crude oil from the decayed remains of i________ and other organic material
has taken place over the last 65 million years. Crude oil forms when organic matter is buried
deep underground in an oxygen free environment. Over millions of years the carbon rich
compounds from the bodies of dead organism are subjected to h_____ and pressure which
changed them into hydrocarbons. Natural gas (mainly methane CH4), an important fossil fuel is
also found trapped with crude oil under rock sediments. Why do we call crude oil a fossil
fuel ?
Word bank: insects heat
Formation of crude oil: rich with life
Waters Dead matter falls Oils layers form
Surface water
Oxygen free layer
Sedimentary rock
Notes The warm seas over areas When these animals died they Over many millions of years,
like Saudi Arabia of 65 sank to the sea bottom. Over heat and pressure over time
million years ago were time carbon rich sediments changes these compounds into
teeming with organisms rich containing many carbon rich carbon rich hydrocarbons now
in the element carbon. biological molecules formed. known as crude oil.
5. Science Interactive LTD Copyright 2005
Fossils fuels and crude oil
A fossil fuel is a substance like o____ or coal that is rich in the element c_______, can be
combusted readily with oxygen and produces energy in the form of h____. They are fossil fuels
because they are formed from once living organisms with solar energy being the original
e_______ source. Fossil fuels are a non-renewable resource, because it takes millions of years
for them to form and we currently combust them faster than they are formed ! Fossil fuels are
also a finite energy resource, because they will eventually run out ! How will this change our
way of living ?
Types of fossil fuels: Word bank: oil carbon heat energy
Crude oil Coal Peat
Diagram
Source Remains of dead insects and Remains of dead plants More recent remains of dead
other organic material plants
Life 60-70 years 300 years 10-15 years
expectancy
6. Science Interactive LTD Copyright 2005
Extraction, transport and storage of crude oil
Crude oil, natural gas or coal can be extracted from under the sea or land, where they have
remained trapped for millions of years. Companies like Shell and BP have invested billions of
pounds exploiting oil r__________ under the North Sea, just off the coast of Scotland. The
North Sea has about 45 oil platforms producing up to four million barrels a day. England has
sufficient oil reserves meeting its current demand for the next forty years. Why is the price of
oil likely to increase over the next 10 years ?
Getting crude oil to the refinery: Word bank: reserves
Extraction Transport Storage
Diagram
Notes Oil is trapped under Oil is transported by ship or Oil is stored at refineries usually
sedimentary rock under the pipeline. This is the most by the coast. We use about 5
oceans and seas. Drilling is economic form of transport. million barrels a day. Oil will
from a floating platform. The Transportation by this method finally run out in around 60-80
North sea has about 45 oil does have its risks. Explain what years. Explain what consequences
platforms producing up to 4 these risks are and look for the this might have and what energy
million barrels a day. Exxon Oil Disaster. alternatives we can use ?
7. Science Interactive LTD Copyright 2005
Processing of crude oil
Crude oil, once it has been extracted from underneath the bedrock, has to be processed to be
useful. Close to where it is stored, oil refineries process crude oil so that it can be more useful
to us. There is a great demand for fuels like petrol and d_________ and of course natural gas
for heating. There is less of a demand for the large hydrocarbons that make up the lubricating
oils. These refineries produce large amounts of p__________. Why is the demand for fuels and
natural gas very high in Europe and England ?
Processing crude oil: Word bank: diesel pollution
Oil refinery Distillation End Product
Diagram
Notes Oil refineries process millions Distillation by these huge Companies like Shell and BP
of barrels of crude oil every fractionating columns separates sell millions of litres of fuels
year to provide for the high out hydrocarbons based on their like petrol and diesel to over 40
demand for fuels like petrol boiling points. Natural gas has million drivers of cars, lorries
and diesel. the lowest boiling point. and vans in the UK.
8. Science Interactive LTD Copyright 2005
Fractional distillation of crude oil
Crude oil is a mixture of different hydrocarbons. They can be separated by fractional
distillation according to their b_______ point which change according to their size (carbon
atoms) The most volatile fraction, i.e with the lowest boiling point evaporates off first and goes
to the top of the c________. The remaining, longer chain hydrocarbons also separate out
according to their boiling points. Word bank: boiling column lubricating
Fractionating column Carbon atoms Boiling points Use
LPG gas C1 – C4 < 40oC Highly flammable gas fuel
Boiling points and viscosity.
Petrol C5 – C10 40oC – 200oC Car fuel
Naphtha C10 – C12 125oC – 175oC Valuable source of organic molecules
Paraffin C12 – C16 175oC – 275oC Less flammable than petrol, domestic
heater fuel
Diesel C16 – C30 235oC – 300oC Larger vehicle fuels
Fuel oil C30 – C100 >300oC Not as flammable, used for central
heating oil and l_________ oils
Crude oil
Bitumen C100 – C300 > 350oC Forms a thick, black, tough and
resistant adhesive layer on cooling.
Used to lay roads.
Heat (400oC)
9. Science Interactive LTD Copyright 2005
Separating hydrocarbons
Fractional distillation of crude oil, a mixture of hydrocarbons is able to separate different
‘fractions’ based on their boiling points. The l_______ the chain, the higher the boiling
point. Methane, ethane and propane, all short chained hydrocarbons have very low boiling
points, whereas hydrocarbons containing a hundred of more carbon atoms have relatively
h_____ boiling points. How can differences in boiling points be used to separate different
alkanes ?
Distillation and fractional distillation: Word bank: longer high
Distillation Crude oil distillation Hydrocarbons
Diagram CH4
C2H6
C3H8
C4H10
C5H12
C6H14
C8H18
C10H22
Notes In the laboratory we can An industrial fractionating Hydrocarbons are separated
separate different liquids from a column separating different into their fractions. Methane
‘mixture’ based on their hydrocarbons based on with the lowest boiling point
different boiling points. What is their boiling points and is separated first at a
the role of the condenser ? number of carbon atoms. temperature of around 40oC.
10. Science Interactive LTD Copyright 2005
Hydrocarbons in crude oil
Crude oil contains two families of hydrocarbon compounds: The alkanes and alkenes. The
alkanes have a general formula of CnH2n + 2 and are used mainly as fuels for combustion with
o______. They include methane (natural gas), the simplest alkane with the formula CH 4.
Alkanes can have up to 200 carbon atoms in a long carbon chain, but their general formula
does not change. Longer chains are used for diesel engines, lubricating oils and domestic
h________ fuels. Alkanes with more than 100 carbon atoms are found in bitumen or tar.
The alkanes: Word bank: oxygen heating
Name Formula Diagram Name Formula Diagram
Methane CH4 Pentane C5H12
Ethane C2H6 Hexane C6H14
Propane C3H8 Octane C8H18
Butane C4H10 Decane C10H22
11. Science Interactive LTD Copyright 2005
Combustion of methane
Useful alkanes include natural gas, petrol and diesel. When we combust these fuels with
o________, energy in the form of h____ and light is released. The products of complete
combustion are water and carbon dioxide. If insufficient oxygen from the atmosphere is
supplied during combustion, what might form instead of carbon dioxide ?
CH4 + 2O2 CO2 + 2H2O
Methane Oxygen Carbon dioxide Water
Combustion of methane: Word bank: oxygen heat
Natural gas Substrates Reaction mixture Products
Diagram
CH4 O
H H
O C02
O2 O H
C H
O2 O
H2O H2O
Notes Natural gas is extracted Methane is rich in carbon During combustion, The products of methane
from underneath the and is a store of ancient new products are combustion with oxygen
bedrock, It is often chemical energy. During formed. The methane are water (H2O) and
found with crude oil its combustion with (CH4) molecules breaks carbon dioxide. (C02) If
deposits. The UK oxygen, it releases its apart and forms new there is not enough
obtains its gas from the energy in the form of bonds with the oxygen oxygen carbon monoxide
North Sea. heat and light. atoms. can form.
12. Science Interactive LTD Copyright 2005
Combustion of the alkanes
Most vehicles use petrol or diesel as a fuel. When we combust these hydrocarbon fuels
with o_______, energy in the form of h____ and motion is released. New substances are
also produced including carbon dioxide and water.
Equation:
2C8H18 + 25O2 CO2 + 18H2O
Octane Oxygen Carbon dioxide Water
Combustion of octane in the car engine: Word bank: oxygen heat
Car engine Octane & Oxygen Engine Products
Diagram
Notes With over 30 million In the engine, huge The engine is designed to The waste products are
cars in the UK, petrol amounts of oxygen are converted the chemical carbon dioxide and water.
rich in octane (C8H18) combined with octane. engine contained in However, un-combusted
is used as a source of This releases all the octane to forward carbon and carbon mon-
chemical energy. Find stored chemical energy motion. It is highly oxide are also released
out the current cost of contained in carbon inefficient releasing only into the environment as
litre of petrol ? rich petrol. 13% of the energy. polluting gases.
13. Science Interactive LTD Copyright 2005
Supply and demand of crude oil fractions
There is a greater demand by those who use fossil fuels for the low carbon, more volatile
hydrocarbons which are used for f____ in cars, p_____ and lorries. However, there is a
greater supply of the high carbon, less volatile hydrocarbons. By breaking up the surplus
large fractions to form small volatile fractions, companies like Shell and BP can balance
s______ and demand. This is called cracking.
Meeting demand from crude oil: Word bank: fuels planes supply
LPG gas Petrol fuel Paraffin Diesel Tar or Bitumen
-100%
% of total crude oil
-80%
-60%
supply
-40% demand supply demand
supply supply demand
-20%
demand demand
-0% supply
LPG Gas Petrol Paraffin Diesel Residue
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Cracking long chain hydrocarbons
Crude oil contains far too many long chained h_________ with more than 15 carbon atoms in
them. Longer hydrocarbons do not make efficient fuels. Cracking is also used to form ethene,
the starting product for most plastics and other polymers. We can s_____ long chain molecules
into short chained molecules. Cracking these hydrocarbons requires heat, a catalyst and an
o________ free atmosphere. Why do you need to exclude oxygen from the cracker ?
Producing short chained hydrocarbons: Word bank: split oxygen
Industrial cracking of crude oil Closer look at cracking
C10H22 Decane
Useful products
Short chained
Alkanes & alkenes
Crude oil and catalyst
are recycled at 400oC
C2H4 Ethene
C3H6 Propene
Crude oil
C5H12 Pentane
Heat (400oC) Cracker
15. Science Interactive LTD Copyright 2005
The alkenes
The alkenes have a general formula of CnH2n and are used mainly for the manufacture of
polymers. Each alkene has a carbon-carbon double bond (C=C) which can be broken by
other atoms like h________ or chlorine added across the double bond. Polymers, made
from simple alkenes are extremely long chained hydrocarbon molecules. The simplest
alkene is ethene with the formula C2H4.
Word bank: hydrogen
The alkenes:
Name Formula Diagram Structural Diagram
Ethene C2H4 H H
C =C
H H
Propene C3H6 H H
C=C C H
H H H
Butene C4H8 H H
H C C=C C H
H H H H
Pentene C5H10 H H H
H C C=C C C H
H H H H H
16. Science Interactive LTD Copyright 2005
Producing ethane from ethene
Unsaturated e_______ (C2H4) can also react with the gas h________ to form the alkane
ethane (C2H6) In this case, ethene in changing to ethane, becomes fully saturated. This
reaction requires h________, a nickel catalyst and an oxygen free atmosphere. The ethene
molecule is much more reactive then the ethane molecule because it has the carbon-carbon
double bond. Why do we call ethene and the alkenes unsaturated and ethane and the
alkanes saturated ?
Addition of hydrogen to ethene: Word bank: ethene hydrogen
Ethene (Alkene) Hydrogen (from water) Ethane (Alkane)
Diagram
Equation C2H4 + H2 C2H6
The two hydrogen atoms join the ethene molecule across the double bond forming
the saturated alkane, ethane.
17. Science Interactive LTD Copyright 2005
Chemical test for the alkenes
Hydrocarbons like the alkenes with a double carbon-carbon bond are called unsaturated.
Alkenes with their double bond are much more r________ that the alkanes. Other elements like
hydrogen and chlorine can be added to alkenes by breaking the double bond. Testing for
alkenes: If you shake up an alkene with a solution of brown bromine water, then the bromine
water appears to lose it’s colour. The double bond in the alkene breaks open and forms new
bonds with the b_______ atoms. This type of reaction is called an addition reaction. Olive oil
but not butter decolourises bromine water what does this tell you about the two types of fat ?
Testing for alkenes: Word bank: reactive bromine
Ethene Bromine (in water) di-Bromoethene
Diagram
Equation C2H4 + Br2 C2H4Br2
The ethene molecule contains a carbon-carbon double bond which accepts both bromine atoms.
When the bromine atoms join the ethene molecule the bromine water loses its brown colour.
18. Science Interactive LTD Copyright 2005
Using ethene to form plastics
Ethene (C2H4) monomers can be joined together to make a polymer called polythene.
Polythene contains huge molecules that act like fibres that can be used as alternatives to
natural materials like w____, paper and metals. Polythene is also very cheap to
manufacture whilst crude oil remains plentiful and the quality is always the same after its
manufacture. Explain why it is beneficial to the environment to use plastics rather than
natural materials like wood, paper and metals ?
Manufacturing plastic or polythene from ethene: Word bank: wood
Ethene (C2H4) Polymerisation reaction Polythene (nC2H4)
Diagram +
+
+
+
Notes Ethene (C2H4) is produced In the presence of a metal Polythene has the general
in large amounts by catalyst, molecules of ethene formula nC2H4. Molecules
cracking long chain add to one another forming can contain up to 50,000
hydrocarbons found in long chained polymers with carbon atoms. These chains
crude oil. the formula nC2H4 behave like fibres.
19. Science Interactive LTD Copyright 2005
Using plastics in everyday life
Polymers like polythene, polyvinylchloride (PVC) and nylon have replaced natural materials
like paper, wood, glass and ceramic. Plastics are c_______, readily available, tough,
waterproof and flexible. They are produced in huge quantities and are used in everyday life
from the humble plastic bag to replacement h____ and bone joints. Although using plastics
instead of glass, paper and wood actually saves energy and rainforests, they are not
biodegradable so their use adds many thousands of tonnes of rubbish per year to landfill sites.
Using plastics: Word bank: cheap hip
Making polythene The plastic bag Saving energy
Diagram
Notes Here we see polythene made from the The plastic shopping bag Recycle
polymerisation of the alkene ethene. made from polythene has
Huge sheets of polythene like the one saved thousands of trees
Reduce
pictured above are manufactured from which would have been used Replace
combining alkene monomers. for making paper. Plastic We can all make less of an
Polythene is used for food wrapping, takes a long time to decay impact on the environment in
packaging and plastic bags. once thrown away. our daily lives.
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The carbon cycle
All living organisms require the element c_________ to make carbohydrates, proteins and
other important molecules which make up living organisms. Cellular respiration and
decomposition by bacteria releases carbon dioxide into the atmosphere. Plants use this during
p____________ at the same rate. The amount of carbon dioxide in the atmosphere should stay
the same but it is increasing rapidly because of the use of fossil fuels and deforestation.
The carbon cycle: Word bank: carbon photosynthesis
Atmosphere Respiration
CO2 Atmosphere
There is 750 billion tonnes of CO2 trapped in the
atmosphere. This is rising by 3 billion tonnes a
year because of fossil fuel use and deforestation.
Fossil fuel combustion Land deforestation Photosynthesis
Plant biomass
Soil Ocean
Buried fossil fuels Marine biomass
There is 3300 billion tonnes of carbon trapped in oil, coal There is 1020 billion tonnes of carbon trapped in living
and natural gas deposits found under rock sediments. organisms like algae. CO2 is also dissolved in the oceans.
21. Science Interactive LTD Copyright 2005
Pollution using crude oil
The oil industry, including companies like Shell and Exxon have a responsibility to make
sure that their company and staff do not p_______ the environment. Occasionally, either
during extraction, transport or s_______ of crude oil, these companies can pollute the
environment with devastating consequences. An oil tanker spilling its load at sea or near to
populated coastlines can destroy the local ecosystems and peoples’ livelihoods. These
effects can sometimes last for many decades. Go to google.co.uk and type in and search
for ‘Exxon Valdize’
Impacting on the environment: Word bank: pollute storage
Tanker spills Oil depot fires Oil spills on land
Diagram
Notes Releasing millions of barrels Fires involving crude oil Crude oil coats every living
of thick poisonous crude oil releases thick black toxic smoke organisms that it comes in
into the oceans means death to into the environment causing contact with. Birds are
many species in the ocean’s widespread pollution and especially vulnerable with their
food chains and webs. damage over a large area. delicate feathers.
22. Science Interactive LTD Copyright 2005
Fossil fuels greenhouse effect
Over the last century, our use of fossil fuels has released huge amounts of carbon dioxide into
our atmosphere. This has disrupted the b_________ between carbon in the form of carbon
dioxide and carbon found tied up under rock in crude oil, natural gas and coal. Currently we
are adding an extra 3 billion tonnes of carbon each year into the atmosphere. The carbon
dioxide molecule traps infra red h_____ from the sun. Slowly our planet is warming because of
the rising carbon dioxide levels. How can you reduce your dependence on fossil fuels like
petrol and natural gas ?
The greenhouse effect: Word bank: balance heat
World’s crude oil use Rising levels of carbon dioxide The greenhouse effect
So
l r
lar
ra
ad
Absorbed in atmosphere
iat
i
by greenhouse gases
o
on
ce
a
sp
o
tt
ou
ted
di a
Ra
15
15 50
50
Altitude (km)
The World’s energy demand and There are over 500 million cars, Carbon dioxides traps heat
the use of crude oil is increasing. all pumping out carbon dioxide energy from the sun. The amount
China in the next two decades from the combustion of octane or of carbon dioxide in the
will use more than the USA. petrol. Car use is set to double atmosphere is increasing by 3
over 20 years. billion tonnes a year.
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Effects of global warming one
Scientists have many theories as to what may happen over the next century because of rising
carbon dioxide levels in the a__________, as a result of combusting fossil fossils and the
subsequent rising global temperatures. There is now increasing agreement amongst scientists
that atmospheric carbon dioxide levels need to be controlled. Many countries have signed ‘The
Kyoto Agreement’ which aims to reduce carbon emissions over the next 20 years. This will
perhaps s____ global warming. Only one country, America has not signed up, she is the biggest
carbon polluter. Why do you think that America has not signed up ?
Effects of global warming: Word bank: atmosphere slow
Global warming Drought Ozone layer Flooding
Diagram
Notes Average world or More extremes of The destruction of the Flooding will increase
global temperatures are temperatures are now Ozone by CFCs from over the next decade. In
set to increase by expected with lower aerosols will also add to England (summer 2004),
between 0.5 and 1oC rainfall in areas which global warming by we had some of the worst
per decade for the next already see little rain reflecting less infra red flash floods on record,
fifty years. over the year. heat given out by the including Boscastle.
sun.
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Effects of global warming two
The greenhouse effect is a natural process where the 750 billions tonnes of c________
dioxide in the atmosphere maintains the Earth’s atmosphere at hospitable temperatures,
which are supportive of life, here on Earth. Combusting fossil fuels is adding to this
‘warming effect’ causing average global t___________ to rise over the last fifty years.
Global warming will continue, whilst we continue to combust fossil fuels like coal and oil.
The World’s weather, habitats and temperature are set to change over the next century.
Effects of global warming: Word bank: carbon temperatures
Weather Waves Biodiversity Melting ice caps
Diagram
Notes The World’s weather Damage due to strong Animals and plants may The ice caps have shrunk
will become more tides and wave action undergo mass extinction in size over the last 30
dynamic. In summer along the coast will in the next one hundred years. This may rise sea
2004, Florida in also increase over the years if global warming levels and also reduce
America was hit by next decade. Parts of continues. The Malarial the amount of the Sun’s
three hurricanes causing the England's coastline Mosquito is spreading infra red heat reflected
immense damage. are now being eroded. north into Europe. back into space.
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Acid rain and fossil fuels
Carbon dioxide is not the only pollutant that is released into the environment during the
combustion of fossil fuels. Sulphur and nitrogen, in small quantities are also present in
crude oil. During combustion, both s_______ and nitrogen combine with oxygen to form
sulphur dioxide and nitrogen oxides. These gases form weak acids when they react with
water present in the atmosphere. Acid rain can damage f________ and plant life. It can
also acidify lakes and ponds disrupting natures balance.
Acid rain: Word bank: sulphur forest
Polluting the Earth’s atmosphere pH of precipitation across America
Diagram
Notes With 280 million Americans each using on The pH of rainfall is lowest where you find the highest
average a staggering 3kw per hour every day population across the East Coast of America. Almost 150
of the year, the amount of Sulphur dioxide million Americans live, work, drive and pollute in this
gas emitted per year for ever square area. The pH of rain water in some areas of the Eastern
kilometre of land is around 0.4 of a tonne. USA seaboard has a very acidic pH of 4.2.
26. Science Interactive LTD Copyright 2005
Acid rain and the atmosphere
In addition to releasing carbon dioxide, small amounts of sulphur and nitrogen, present as impurities
in crude oil cause other polluting gases to be released into the atmosphere. During combustion, both
sulphur and nitrogen combine with o________ to form sulphur dioxide and nitrogen oxides. These
gases form weak acids when they react with water in the atmosphere. Acid rain can damage forests
and plant life. It can also acidify lakes and ponds disrupting natures balance.
Acid rain cycle: Word bank: oxygen
Diagram
Rain cloud
S02 & NOx react with
water to form acid rain.
SO2 NOx H SO
2 4 HNO3
Sulphuric acid Nitric acid
Acid Rain Acid Rain Acid Rain
Power station Combustion engines Acidified soil Acidified lake Damaged forests
Notes The combustion of fossils fuels releases SO2 and NOx into the atmosphere. These gases on contact
with water vapour form sulphuric and nitric acid. Acid rain can damage forests, acidify the soil and
reduce the pH of lakes, ponds and rivers. Rain clouds containing low pH rain water can travel
many kilometres. Due to England's westerly winds, our acid rain travels to our European
neighbours including Sweden and Denmark.
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Acid rain and fossil fuels
Carbon dioxide is not the only pollutant that is released into the environment during the
combustion of fossil fuels. Sulphur and nitrogen are also present in crude oil. During
combustion, both sulphur and nitrogen combine with oxygen to form sulphur dioxide and
nitrogen oxides. These gases form weak a_____ when they react with water in the atmosphere.
Acid rain can damage forests and plant life. It can also acidify l______ and pond disrupting
natures balance. Look at this statue and notice the chemical weathering !
Acid rain and its effects: Word bank: acids lakes
Acid rain damage to forests Acid rain damage to waterways Acid rain damage to marble
Diagram
Notes Forests and all plant life are Rivers, ponds and lakes can Acid rain also destroys buildings
sensitive to acid rain even over become acidic in areas with high and statues made from limestone
short periods of time. The rainfall levels. Low pH of the or marble. Dissolved acid in
delicate leaves are damaged by water can lead to the disruption of raindrops reacts with the calcium
the low pH rainfall. When a tree the ecosystem, therefore killing carbonate in the marble or
loses its leaves due to acid rain, many species. How can scientists limestone making a soluble
it can no longer produce its neutralise acidic lakes, what product calcium oxide. This is
own food during chemical would they use ? slowly dissolved away by rainfall.
photosynthesis.
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Renewable energy sources
Renewable alternatives to using crude oil for generating electricity are now being
developed. These reduce our dependence on crude oil, as well as reducing carbon dioxide
emissions. Many sources of e_______ that we currently use every day are now renewable.
This means that unlike coal, natural gas and crude oil they are not used up. Many
scientists are working to develop the technology to use these renewable sources of energy
to generate e__________.
Overview of renewable energy: Word bank: energy electricity
Wind Solar Biogas Hydroelectric
Wind farms could supply Solar cells using solar Converting animal waste like Using moving water, hydro-
up to 15% of the energy energy could power traffic manure from farms and electric dams are able to
we use every year. Why lights and street lamps. farming into methane using generate clean electricity.
do people in the They are only useful in bacteria is a way of replacing The only problem is that you
countryside object to countries with high rates fossil fuels like gas. Give the need lots of space and high
these wind farms ? of sunshine. formula of methane ? yearly rainfall.
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Generating electricity using wind power
Wind power stations makes use of the k_______ energy of moving air currents. Kinetic
energy directly drives small generators that produce electricity. Wind farms are usually
found in windy unpopulated areas. Several w_____ turbines can supply, on a windy day
enough energy for a small town. This is a clean, renewable form of energy with limited
drawbacks. Some people object to the ‘visual pollution’ that many wind turbines cause and
believe they spoil the landscape. Why do you need large areas of land to generate
electricity using wind power ?
Wind power supplying electricity: Word bank: kinetic wind
Diagram
Notes Captured kinetic energy of the wind drives the generator, producing electricity. Using wind
turbines is still expensive and is only viable in countries with large amounts of free land and of
course windy weather. The energy is totally renewable and does not increase the levels of polluting
gases which add to either global warming or acid rain. The map shows the average wind speed in
America. Where are the best places for a wind farm....Explain your answer ?
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Generating electricity using solar power
Solar power can be used directly to generate small amounts of electricity using photovoltic
cells. These produce a low c________ and are only useful for producing electricity in remote
areas or for devices that only require a low current, for example calculators. Using solar power
to heat water creating steam which then drives a turbine generator is another way the sun’s
energy can be used to generate electricity. E_________ regions that receive plenty of sunshine
are ideal. The only problem is that the technology is still relatively expensive. Why is the UK
not an ideal location for solar panels or cells ?
Solar power supplying electricity: Word bank: current equatorial
Diagram
Notes Steam produced from the heat energy collected by solar reflectors drives the turbine and generator.
A current is induced in the cables. Electricity is transported to commercial and domestic users.
Using solar cells is expensive and is only viable in countries with good weather. Solar cells can be
used to directly generate electricity. These are very useful where there is demand for energy in very
remote areas like the desert or away from major towns and cities.
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Generating electricity using biogas
Electricity can be generated on a small scale using biogas. Biogas is exactly the same as
methane, the fossil fuel extracted from underneath the rock, but it is produced by b________
respiring animal wastes like manure. This is therefore a renewable supply of methane gas
which can be used in the same way as fossil fuels, with the h_____ energy used to produce
steam which in turn drives a turbine generator. Why is the amount of electricity generated using
this method very small at present ?
Biogas supplying electricity: Word bank: bacteria heat
Biogas
Diagram Biogas mini power station Waste
Waste
Gases
Gases
Turbine
Turbine
Boiler
Boiler Generator
Generator
Steam
Steam 33,000V
33,000V 240V
240V
Manure
Manure Fermentor
Fermentor Fermentor
Fermentor Furnace
Furnace Transformer 1
Transformer 1 Transformer 2
Transformer 2 Customer
Customer
Notes Steam produced from the heat energy given out when natural gas (CH4) is combusted with oxygen
drives the turbine and generator. A current is induced in the cables. Electricity is transported to
commercial and domestic uses only. Using biogas, although expensive and still producing
greenhouse gases recycles animal waste like manure.
32. Science Interactive LTD Copyright 2005
Generating electricity using gravitational potential energy
Water held behind a dam, stores huge amount of gravitational potential energy. When the
stored water is allowed to flow downhill, its kinetic energy is used to drive turbine generators,
which in turn produces electricity. Hydroelectric dams are usually constructed in mountainous
areas with high yearly rainfall levels. The three gorges dam is the largest r__________ and is
currently under construction in China. When finished, it will generate millions of kilowatts
everyday. Although this is renewable e_______ up to ten million people will be displaced
when the valley is flooded. Why is this technology used only in wet mountainous areas ?
Moving water supplying electricity: Word bank: reservoir energy
Diagram
Notes Large amounts of land and rainfall are required for any hydroelectric dam. The main
advantages of hydroelectricity is that it is a renewable form of energy and the start up time
from allowing the water drop to generating electricity is less than a second. Electrical energy
generated in this way is used to supply electrical power during peak demands.