Crude Oil and its Products

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PO BOX 50764 LONDON NW6 9AT email: sales@science-interactive.co.uk web: www:science-interactive.co.uk Unit 1: The Digestive System Unit 2: The Circulatory System Unit 3: Healthy Body and Immunity Unit 4: The Respiratory System Unit 5: Nervous System and the Senses Unit 6: Human Homeostasis Unit 7: Hormones and the Endocrine System Unit 8: Drugs and Bad Body Maintenance Unit 9: Photosynthesis in Green Plants Unit 10: Water Transport in Plants Unit 11: Flow of Energy and Elements through the Environment Unit 12: Mitosis and Meiosis Unit 13: Inheritance and Selection Unit 14: Evolution and Human Impact Unit 15: Genetic Engineering Unit 20: Crude Oil and its Products Unit 21: Rock Cycle Unit 22: Elements, Molecules and Compounds Unit 23: Ionic and Covalent Compounds Unit 24: The Halogens, their Uses and Compounds Unit 25: The Noble Gases, their Properties and Uses Unit 26: Rates of Reaction Unit 27: Energy Unit 28: Generating Electricity and its Domestic Use Unit 29: Electricity Unit 30: Light and the Electromagnetic Spectrum Unit 31: Radioactivity Unit 32: Newton's Forces and the Effects of Forces Unit 33: Earth and Space Unit 34: The Earth and Plate Tectonics GCSE SCIENCE OCR EDEXCEL AQA Unit 16: The Periodic Table and its Elements Unit 17: The Alkali Metals Unit 35: The Alkaline Earth Metals Unit 36: Sound and Hearing Unit 18: Metals and their Properties Unit 19: The Transitional Metals Unit 37: Natural Forces Unit 38: Cells, Tissue, Organs and Organs systems Science Interactive LTD Copyright 2005   Lesson number 20 Crude Oil and its Products Unit 20: Crude Oil and its Products Science Interactive LTD Copyright 2005 Understand: 1. 2. Keywords: Crude Oil, Formation, Fossil, Fuel, Hydrocarbons, Hydrogen, Carbon, Fractional, Distillation, Alkanes, Alkenes, Cracking, Ethene, Polymers, Plastics, Polymerisation, Greenhouse, Global, Warming & Pollution. 3. 4. 5. 6. 7. 8. 9. 10. 11. How crude oil and other fossil fuels rich in carbon were formed. That crude oil is a mixture of hydrocarbons. That hydrocarbons contain only two elements: hydrogen and carbon. That different hydrocarbons have different uses and can be separated using fractional distillation. That the alkane family of hydrocarbons are used mainly as fuels by transport vehicles. The chemical properties of the alkanes and the alkenes. The use of ethene and other alkenes in the formation of polymers and plastics. The benefits and costs of using crude oil as fuels and as a starting material for the manufacture of plastics. That the increases emissions of carbon dioxide in the atmosphere is causing the greenhouse effect. The likely impact of the greenhouse effect. That there are many renewable alternative to using crude oil as an energy source. Click mouse to begin web: www.science-interactive.co.uk email: sales@science-interactive.co.uk Science Interactive LTD PO BOX 50764 LONDON NW6 9AT 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: World oil reserves Diagram Energy use in the modern World Word bank: crude Notes World oil reserves are finite. It estimated that we currently have around 60 – 80 years of crude oil remaining. Saudi Arabia, Iraq and Russia have the largest reserves with over 50 billions barrels of crude oil underground. This composite picture of the world at night shows us the biggest energy users. North America, followed by Europe and Japan are the largest users or energy. These countries depend most on the ‘cheap energy’ that crude oil provides us. 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 ? Formation of crude oil: Waters rich with life Surface water Word bank: insects heat Dead matter falls Oils layers form Oxygen free layer Sedimentary rock Notes The warm seas over areas like Saudi Arabia of 65 million years ago were teeming with organisms rich in the element carbon. When these animals died they sank to the sea bottom. Over time carbon rich sediments containing many carbon rich biological molecules formed. Over many millions of years, heat and pressure over time changes these compounds into carbon rich hydrocarbons now known as crude oil. 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: Crude oil Coal Peat Word bank: oil carbon heat energy Diagram Source Life expectancy Remains of dead insects and other organic material Remains of dead plants More recent remains of dead plants 60-70 years 300 years 10-15 years 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: Extraction Diagram Word bank: reserves Transport Storage Notes Oil is trapped under sedimentary rock under the oceans and seas. Drilling is from a floating platform. The North sea has about 45 oil platforms producing up to 4 million barrels a day. Oil is transported by ship or pipeline. This is the most economic form of transport. Transportation by this method does have its risks. Explain what these risks are and look for the Exxon Oil Disaster. Oil is stored at refineries usually by the coast. We use about 5 million barrels a day. Oil will finally run out in around 60-80 years. Explain what consequences this might have and what energy alternatives we can use ? 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: Oil refinery Diagram Word bank: diesel pollution Distillation End Product Notes Oil refineries process millions of barrels of crude oil every year to provide for the high demand for fuels like petrol and diesel. Distillation by these huge fractionating columns separates out hydrocarbons based on their boiling points. Natural gas has the lowest boiling point. Companies like Shell and BP sell millions of litres of fuels like petrol and diesel to over 40 million drivers of cars, lorries and vans in the UK. 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. Fractionating column LPG gas Carbon atoms Boiling points Use Word bank: boiling column lubricating C1 – C4 < 40oC Highly flammable gas fuel Boiling points and viscosity. Petrol C5 – C10 40oC – 200oC Car fuel Naphtha C10 – C12 Paraffin Diesel Fuel oil C12 – C16 C16 – C30 C30 – C100 125oC – 175oC Valuable source of organic molecules 175oC – 275oC Less flammable than petrol, domestic heater fuel 235oC – 300oC Larger vehicle fuels >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) 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: Distillation Diagram Word bank: longer high Crude oil distillation Hydrocarbons CH4 C2H6 C3H8 C4H10 C5H12 C6H14 C8H18 C10H22 Notes In the laboratory we can separate different liquids from a ‘mixture’ based on their different boiling points. What is the role of the condenser ? An industrial fractionating column separating different hydrocarbons based on their boiling points and number of carbon atoms. Hydrocarbons are separated into their fractions. Methane with the lowest boiling point is separated first at a temperature of around 40oC. Hydrocarbons in crude oil Science Interactive LTD Copyright 2005 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 CH4. 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: Name Methane Word bank: oxygen heating Formula Diagram Name Formula Diagram CH4 Pentane C5H12 Ethane C2H6 Hexane C6H14 Propane C3H8 Octane C8H18 Butane C4H10 Decane C10H22 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 Methane + 2O2 Oxygen CO2 + 2H2O Water Word bank: oxygen heat Carbon dioxide Combustion of methane: Natural gas Diagram CH4 O O2 C O H H Substrates Reaction mixture O H Products C02 H O2 Notes Natural gas is extracted from underneath the bedrock, It is often found with crude oil deposits. The UK obtains its gas from the North Sea. Methane is rich in carbon and is a store of ancient chemical energy. During its combustion with oxygen, it releases its energy in the form of heat and light. O H2O H2O During combustion, new products are formed. The methane (CH4) molecules breaks apart and forms new bonds with the oxygen atoms. The products of methane combustion with oxygen are water (H2O) and carbon dioxide. (C02) If there is not enough oxygen carbon monoxide can form. 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 Octane + 25O2 Oxygen CO2 + Carbon dioxide 18H2O Water Word bank: oxygen heat Combustion of octane in the car engine: Car engine Octane & Oxygen Engine Products Diagram Notes With over 30 million cars in the UK, petrol rich in octane (C8H 18) is used as a source of chemical energy. Find out the current cost of litre of petrol ? In the engine, huge amounts of oxygen are combined with octane. This releases all the stored chemical energy contained in carbon rich petrol. The engine is designed to converted the chemical engine contained in octane to forward motion. It is highly inefficient releasing only 13% of the energy. The waste products are carbon dioxide and water. However, un-combusted carbon and carbon monoxide are also released into the environment as polluting gases. 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: LPG gas Petrol fuel Paraffin Diesel Word bank: fuels planes supply Tar or Bitumen -80% -60% -40% % of total crude oil -100% demand supply supply demand -20% supply supply demand demand demand -0% supply LPG Gas Petrol Paraffin Diesel Residue Science Interactive LTD Copyright 2005 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: Industrial cracking of crude oil Useful products Short chained Alkanes & alkenes Word bank: split oxygen Closer look at cracking C10H22 Decane Crude oil and catalyst are recycled at 400oC C2H4 Ethene C3H6 Propene Crude oil C5H12 Pentane Heat (400oC) Cracker The alkenes Science Interactive LTD Copyright 2005 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. The alkenes: Name Ethene Word bank: hydrogen Formula Diagram Structural Diagram H C=C H C2H4 C3H6 C4H8 C5H10 H H H C=C C H Propene H H H H H H H Butene H H H H C C=C C H Pentene H H H H H H H H H C C=C C C H 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: Ethene (Alkene) Diagram Hydrogen (from water) Ethane (Alkane) Word bank: ethene hydrogen Equation C2H4 + H2 C2H6 The two hydrogen atoms join the ethene molecule across the double bond forming the saturated alkane, ethane. 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: Ethene Bromine (in water) di-Bromoethene Word bank: reactive bromine 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. 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: Ethene (C2H4) Diagram Polymerisation reaction Polythene (nC2H4) Word bank: wood + + + + Notes Ethene (C2H4) is produced in large amounts by cracking long chain hydrocarbons found in crude oil. In the presence of a metal catalyst, molecules of ethene add to one another forming long chained polymers with the formula nC2H4 Polythene has the general formula nC2H4. Molecules can contain up to 50,000 carbon atoms. These chains behave like fibres. 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: Making polythene The plastic bag Saving energy Word bank: cheap hip Diagram Notes Here we see polythene made from the polymerisation of the alkene ethene. Huge sheets of polythene like the one pictured above are manufactured from combining alkene monomers. Polythene is used for food wrapping, packaging and plastic bags. The plastic shopping bag made from polythene has saved thousands of trees which would have been used for making paper. Plastic takes a long time to decay once thrown away. Recycle Reduce Replace We can all make less of an impact on the environment in our daily lives. Science Interactive LTD Copyright 2005 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: Atmosphere Word bank: carbon photosynthesis 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. Respiration Fossil fuel combustion Land deforestation Plant biomass Photosynthesis Soil Buried fossil fuels Ocean 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. 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: Tanker spills Diagram Oil depot fires Oil spills on land Word bank: pollute storage Notes Releasing millions of barrels of thick poisonous crude oil into the oceans means death to many species in the ocean’s food chains and webs. Fires involving crude oil releases thick black toxic smoke into the environment causing widespread pollution and damage over a large area. Crude oil coats every living organisms that it comes in contact with. Birds are especially vulnerable with their delicate feathers. 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: World’s crude oil use Rising levels of carbon dioxide Word bank: balance heat The greenhouse effect Absorbed in atmosphere by greenhouse gases 15 15 50 50 Altitude (km) The World’s energy demand and the use of crude oil is increasing. China in the next two decades will use more than the USA. There are over 500 million cars, all pumping out carbon dioxide from the combustion of octane or petrol. Car use is set to double over 20 years. Carbon dioxides traps heat energy from the sun. The amount of carbon dioxide in the atmosphere is increasing by 3 billion tonnes a year. Science Interactive LTD Copyright 2005 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: Global warming Diagram Drought Ozone layer Word bank: atmosphere slow Flooding Notes Average world or global temperatures are set to increase by between 0.5 and 1oC per decade for the next fifty years. More extremes of temperatures are now expected with lower rainfall in areas which already see little rain over the year. The destruction of the Ozone by CFCs from aerosols will also add to global warming by reflecting less infra red heat given out by the sun. Flooding will increase over the next decade. In England (summer 2004), we had some of the worst flash floods on record, including Boscastle. Science Interactive LTD Copyright 2005 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: Weather Diagram Word bank: carbon temperatures Waves Biodiversity Melting ice caps Notes The World’s weather will become more dynamic. In summer 2004, Florida in America was hit by three hurricanes causing immense damage. Damage due to strong tides and wave action along the coast will also increase over the next decade. Parts of the England's coastline are now being eroded. Animals and plants may undergo mass extinction in the next one hundred years if global warming continues. The Malarial Mosquito is spreading north into Europe. The ice caps have shrunk in size over the last 30 years. This may rise sea levels and also reduce the amount of the Sun’s infra red heat reflected back into space. Science Interactive LTD Copyright 2005 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: Polluting the Earth’s atmosphere Diagram Word bank: sulphur forest pH of precipitation across America Notes With 280 million Americans each using on average a staggering 3kw per hour every day of the year, the amount of Sulphur dioxide gas emitted per year for ever square kilometre of land is around 0.4 of a tonne. The pH of rainfall is lowest where you find the highest population across the East Coast of America. Almost 150 million Americans live, work, drive and pollute in this area. The pH of rain water in some areas of the Eastern USA seaboard has a very acidic pH of 4.2. 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: Diagram Rain cloud Word bank: oxygen SO2 NOx S02 & NOx react with water to form acid rain. H2SO4 Sulphuric acid HNO3 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. Science Interactive LTD Copyright 2005 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: Acid rain damage to forests Acid rain damage to waterways Word bank: acids lakes Acid rain damage to marble Diagram Notes Forests and all plant life are sensitive to acid rain even over short periods of time. The delicate leaves are damaged by the low pH rainfall. When a tree loses its leaves due to acid rain, it can no longer produce its own food during photosynthesis. Rivers, ponds and lakes can become acidic in areas with high rainfall levels. Low pH of the water can lead to the disruption of the ecosystem, therefore killing many species. How can scientists neutralise acidic lakes, what chemical would they use ? Acid rain also destroys buildings and statues made from limestone or marble. Dissolved acid in raindrops reacts with the calcium carbonate in the marble or limestone making a soluble product calcium oxide. This is slowly dissolved away by rainfall. Science Interactive LTD Copyright 2005 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: Wind Solar Biogas Word bank: energy electricity Hydroelectric Wind farms could supply up to 15% of the energy we use every year. Why do people in the countryside object to these wind farms ? Solar cells using solar energy could power traffic lights and street lamps. They are only useful in countries with high rates of sunshine. Converting animal waste like manure from farms and farming into methane using bacteria is a way of replacing fossil fuels like gas. Give the formula of methane ? Using moving water, hydroelectric dams are able to generate clean electricity. The only problem is that you need lots of space and high yearly rainfall. Science Interactive LTD Copyright 2005 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: Diagram Word bank: kinetic wind 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 ? Science Interactive LTD Copyright 2005 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: Diagram Word bank: current equatorial 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. Science Interactive LTD Copyright 2005 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: Diagram Biogas Biogas mini power station Waste Waste Gases Gases Word bank: bacteria heat Turbine Turbine Boiler Boiler Steam Steam Generator Generator 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. 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: Diagram Word bank: reservoir energy 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. Science Interactive LTD Copyright 2005 Extension questions and homework 1: 2: Define the following terms: Cracking, Distillation, Separation, Alkene, Alkane, Saturated and Unsaturated. Look at the three pictures below. Complete the table. Picture Car Plane Cooker Fuel type (alkane) Formula 3: Answer the following: a) Give 5 uses of oil in the modern industrial world. b) How does the volatility and flammability of the alkanes change as the carbon chain increases its length. c) Which fractions will ignite most easily and why. d) Cracking large molecules of alkanes is very important. Give two reasons why and give an example of a large molecule being cracked and its subsequent products. (e.g. C12H26) e) Describe the conditions for cracking and explain why large molecules are heated in the absence of oxygen. f) Explain what is meant by the following sentence: Oil is a finite source what does this mean. Science Interactive LTD Copyright 2005 4: In table 1 the information shows the demand for different fractions of North Seal Oil. a) Why is the demand for diesel oil and residue greater in the winter than the summer. b) Why is the demand for petrol fairly constant all year round. c) What would an oil company do to cope with the changing demand between summer and winter. d) What is bitumen used for and how does its properties fit in with this use. Fraction Refinery gas Gasoline Kerosene Percentage demand in summer 3.6 32 12 Percentage demand in winter 3 29 6 Fraction Diesel oil Residue Bitumen Percentage demand in summer 17 20 15.4 Percentage winter demand 23 22 17 in 5: Answer the following questions: a) Explain what is meant by the following words: Monomer, polymer, polymerization, plastic and polymer. b) What is the polymer of the following monomers: (i) Ethene (ii) Vinyl chloride (iii) Ester. c) Each of the following materials contain fibres or polymers. For each material say whether it is natural or synthetic, being made from crude oil. Wood PVC Linen Polyester Perspex Rayon Lycra Rubber Leather 6: Answer the following questions: a) You often hear chemists say crude oil is too valuable just to burn for heating and transport. Explain why this could be true. b) Give the balanced equation for the complete combustion of a) methane (CH4) and nonane (C9H 20). What are the bonds broken and formed during the reaction. c) Why does plastic present a problem for disposal. What solutions can you think of. d) Some manufactures are making biodegradable plastics. One type used for making shopping bags consists of tiny grains of polythene stuck together with cellulose. Why does this make it biodegradable. Will it degrade completely. e) The price of virtually all plastics depends on the price of crude oil. Explain why this is true. Internet: Go to google.co.uk and find out about the manufacture of nylon. Also visit the website of British Petroleum (bp.com). Where do they extract their crude oil from and which use of crude oil forms their biggest market.