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1 ROTATION 2 Module 3 – 9G Environmental chemistry Lesson Title 1 Acids, alkalis and pH 2 Neutralisation 3 The pH of soils 4 The causes and effects of acid rain 5 The effects of global warming 6 Monitoring pollution Module 4 – 9H Simple chemical reactions Lesson Title 1 History and theory of burning 2 Combustion of magnesium 3 Fuels and their energy release 4 Displacement reactions and their energy release 5 Solubility I 6 Solubility II 7 3 + 4 Module test

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Page 1: ROTATION 2 - webucate.org · Lesson Title 1 Acids, alkalis and pH 2 Neutralisation 3 The pH of soils 4 The causes and effects of acid rain 5 The effects of global warming 6 Monitoring

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ROTATION 2 Module 3 – 9G Environmental chemistry Lesson Title 1 Acids, alkalis and pH 2 Neutralisation 3 The pH of soils 4 The causes and effects of acid rain 5 The effects of global warming 6 Monitoring pollution Module 4 – 9H Simple chemical reactions Lesson Title 1 History and theory of burning 2 Combustion of magnesium 3 Fuels and their energy release 4 Displacement reactions and their energy release 5 Solubility I 6 Solubility II 7 3 + 4 Module test

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Year 9G: Module 3 – Environmental Chemistry Lesson 1 – Acids, alkalis and pH Learning Objectives Pupils should learn: • that solutions can be acidic, alkaline or neutral and can be classified as such by using indicators such as litmus paper and Universal indicator solution/paper • how to use Universal indicator to find the pH of a solution • how to use the pH scale as a measure of acidity and alkalinity of a solution • that alkalis are solutions of metal hydroxides or ammonium hydroxide • be aware that both acids and alkalis can be corrosive National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 3d Key Stage 2 link/Prior learning Sc3 Materials and their properties – 2d & f Pupils will • know how to use universal indictor and may have made an indicator using red cabbage in Year 7 • know about acids and alkalis and possibly some everyday examples Suggested teaching activities Brainstorm with pupils about what they know about acids and alkalis and write on board. Teacher is to demonstrate of litmus solution and litmus papers to identify an acid, alkali or neutral solution. Give definitions of an indicator as something, which is one colour in an acid and another colour in an alkali. Although acids taste sour and alkalis feel slimy these should not be used, as tests to identify them as both acids and alkalis are corrosive. Give advantage of universal indicator, being able to give the strength of an acid or alkali – the strength being represented by the term pH and give pH scale. Practical: Demonstrate and instruct pupils to find out the pH of various solutions: (hydrochloric acid, nitric acid and sulphuric acid, solutions of sodium hydroxide, ammonia, calcium hydroxide (limewater), magnesium hydroxide (milk of magnesia), lemon juice, vinegar, soap, shampoo, washing powder solution, toothpaste, sodium bicarbonate & salt water. Pupils are to dip a glass rod into a particular solution and dot solution onto a piece of universal indicator paper and compare colour with a pH colour chart. Pupils are to record colour of UI paper and assign pH number in a table. Pupils are to conclude whether substances are strong/weak acids or alkalis or even neutral. Give pupils names of common acids and alkalis – alkalis all having hydroxide in their name. If formulae are given, pupils may note that acids contain the element hydrogen. Pupils are to colour in pH chart with numbers and complete worksheet. Instruct pupils to answer questions from core chemistry textbook.

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Extension Pupils could discover what makes substances acid/alkali or neutral i.e. hydrogen ions and hydroxide ions. Look at and learn the chemical formula of acids and alkali: SULPHURIC ACID - H2SO4 NITRIC ACID – HNO3 HYDROCHLORIC ACID - HCl SODIUM HYDROXIDE – NaOH POTASSIUM HYDROXIDE – KOH CALCIUM HYDROXIDE – Ca(OH)2 AMMONIUM HYDROXIDE – NH4OH Resources/References Beakers of hydrochloric acid, nitric acid and sulphuric acid, solutions of sodium hydroxide, ammonia, calcium hydroxide (limewater), magnesium hydroxide (milk of magnesia), lemon juice, vinegar, soap, shampoo, washing powder solution, toothpaste, sodium bicarbonate & salt water, spotting tiles, pipettes, Universal indicator paper, litmus paper, colour/pH chart Worksheets – on pH and acidic and alkali solutions Core chemistry 4.3: How can we tell whether something is an acid? P62-63 Core chemistry C3.5: Acids and alkalis P 152-153 Exploring science book 9: CRd: Bathroom chemistry P112-113 Homework Complete worksheet on acids and alkali or list number of substances used or found in the home and say whether acidic/alkaline or neutral. Safety/Risk Assessment Safety goggles must be worn, as acids/alkalis are corrosive. Pupils must be warned not to taste solutions. Wash any skin in contact with acid/alkali thoroughly with water. Additional Notes Ensure pupils do not contaminate solutions when using the glass rod – pupils must wash with water the glass rod when testing a new solution. Associated Skills: Communication � Application of Number � Information Technology �

Working with Others � Improving own Learning � Problem Solving � Citizenship �

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Year 9G: Module 3 – Environmental Chemistry Lesson 2 – Neutralisation Learning Objectives Pupils should learn: • that when an alkali is added to an acid, neutralisation takes place • how to obtain a neutral solution from an acid and an alkali • the hazards associated with alkali and acids • how to make the fertiliser ammonium sulphate by neutralisation • that some everyday applications of neutralisation e.g. the treatments of indigestion, the treatment of acid soil • that there are many different salts and that many salts are useful National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 3d & f Key Stage 2 link/Prior learning Sc3 Materials and their properties – 2f Pupils will • know about neutralisation and examples of this reaction in year 7 Suggested teaching activities Brainstorm with pupils about what they know about neutralisation – put details on the board along with uses of neutralisation (some everyday applications of neutralisation e.g. the treatments of indigestion, the treatment of acid soil). Explain neutralisation is the chemical reaction between an acid and alkali to produce a salt and water. The final products will be neutral and have a pH of 7. Acid + Alkali salt + water Hydrochloric acid + sodium hydroxide sodium choride + water Teacher is to demonstrate how to conduct practical of neutralisation using sodium hydroxide and hydrochloric acid (use concentrated acid and alkali – 2 Molar). Alternative could be a teacher demonstration only using a burette. Inform pupils that sodium hydroxide is corrosive hence the name caustic soda. Pupils are shown hazard symbol for corrosive and irritant and informed even diluted solutions are skin irritants. Class practical: Hand out worksheet on neutralisation: making sodium chloride (salt) from sodium hydroxide and hydrochloric acid. Pupils are to measure out 10cm3 of dilute hydrochloric acid into a small beaker. Add 3 drops of UI solution and then carefully add sodium hydroxide solution drop by drop until the solution is green. Put 3 spatula measures of charcoal into the beaker and heat over a medium flame until it just boils. Turn off the Bunsen burner and allow it to cool. When cool filter the mixture into an evaporating dish and heat until some of the liquid evaporates. Allow some time to crystallise and examine the product.

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The final substance should be white in colour. Instruct pupils to write the word equation for the reaction and answer questions on the worksheet. Establish with pupils that sodium chloride is commons salt but there are many more salts. Instruct pupils to write word equations for other neutralisation reactions i.e. Potassium hydroxide + sulphuric acid Potassium sulphate + water Ammonia + sulphuric acid Ammonium sulphate + water (Fertiliser) Calcium hydroxide + nitric acid Calcium nitrate + water Instruct pupils to answer questions from core chemistry textbook. Extension Pupils could write formulae and symbol equations for the above neutralisation reactions. Ask pupils to use secondary source to find out the uses of some salts e.g. sodium stearate (soap), magnesium sulphate (Epsom salts), copper sulphate (fungicide), sliver nitrate, calcium sulphate, potassium nitrate, iron sulphate (in iron tablets). Resources/References Class practical for making sodium chloride by neutralisation 1-2 M of hydrochloric acid and sodium hydroxide solution, small beaker, charcoal, filter paper and funnel, Bunsen burner, tripod, gauze, safety mat, matches, evaporating dish, conical flask, crystallising dish, labels, UI solution, pipettes, stirring rods, measuring cylinder Demonstration only Use a burette, flask, clamp stand with the above equipment excluding pipettes Worksheets – neutralisation: making salts Core chemistry 4.4: Getting rid of an acid and alkali P64-65 Core chemistry 4.5: Using neutralisation reactions P66-67 Core chemistry C3.6: Acids in the soil P154-155 Exploring science book 9: 9Ed All about salts P72 Exploring science book 9: 9Ed Metal oxides and acids P70-71 Spotlight science Y9: 34c salt of the earth P136-137 Spotlight science Y9: 34d useful reactions P138-139 Homework Complete worksheet on neutralisation or pupils could research from a secondary source some uses of salts as shown in extension. Safety/Risk Assessment Safety goggles must be worn, as acids/alkalis are corrosive. Pupils must be warned not to taste solutions. Wash any skin in contact with acid/alkali thoroughly with water. Acids and alkali are flammable – ensure pupils are aware to keep both solutions away from flames. Additional Notes Ensure pupils know how to correct if solution when the end point (green colour) is missed during neutralisation process. If solution becomes red add more sodium hydroxide and if solution turns blue

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add more acid drop wise. Heating with charcoal decolourises the UI solution – ensure pupils heating and filter correctly otherwise the final solution contains black solid or is still green. Ensure pupils do not boil off all the water at the end of the reaction to allow large crystals to form. Could use a computer simulation or a pH probe to give accurate readings in a demonstration. Associated Skills: Communication � Application of Number � Information Technology �

Working with Others � Improving own Learning � Problem Solving � Citizenship �

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Year 9G: Module 3 – Environmental Chemistry Lesson 3 – The pH of soils Learning Objectives Pupils should learn: ���� the different types of soils found i.e. clay soil, sandy soil and loam soil � that different soils have different characteristics, including pH ranges which affects the plants that grow in them. � to locate information about plants and preferred soil types from secondary sources. ���� to use knowledge about acids and alkalis and neutralisation to suggest ways of reducing the acidity of soils. National Curriculum references: Keys stage 3 Sc 3 materials and their properties – 3d, 3f & 3g Key Stage 2 Links / Prior Learning Sc3 materials and their properties – 1d Pupils will know •••• about the different types of soils and environments from Unit 3D ‘Rocks and soils’ and Unit 6A 'Interdependence and adaptation’ •••• about acids and alkalis from previous modules taught in Unit 7E ‘Acids and alkalis’ Suggested Teaching Activities Remind pupils about sedimentary rock (show a sample), Sedimentation (broken up bits of rock formed by weathering and erosion) and ask them what else plays a role in soil formation. Establish that soil is a mixture of things which include: broken up bits of rock, sand and clay, decaying remains of plants and animals called humus, air and water, dissolved chemicals, different living things both plants and animals – very important to establish. Brainstorm with pupils about the reasons for different types of soils found around the world. (Could demonstrate different types of soil in a long glass container) Clay soil contains very small particles with little room for air. It is often heavy as it holds water. Sandy soil contains larger particles with lots of room for air. It is light but often dry as water easily runs through it. Loam soil is the best soil for growing soil because it contains a mixture of clay and sand and humus. It is easy to dig, doesn’t get too dry or too wet and plants grow well in it. What could be added to exhausted soil to improve it at home? Compost made up of household rubbish – rotting vegetation, eggshells, sawdust etc. Brainstorm with pupils about what types of plants that will grow in these types of soils and how we could test the soil’s pH. Most soils in the UK are slightly acidic with a pH of 6.0-6.5. We can add water, then filter and then add universal indicator solution to find out pH of the soil. Give pupils information on different plants and their pH range for best growth.

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Plant pH range for best growth

Cabbage/Brussels sprouts 6.0-7.5 Apples 5.0-7.5

Broad beans 5.5-6.5 Potatoes 4.5-6.0 Tomatoes 5.5-7.0

Class practical: (Inform technician about the pH of soil samples you would prefer) Inform pupils that a farmer has sent several soil samples from different fields to a laboratory to be analysed. The farmer would like to know which plants to grow in each field from which soil samples were taken. The pupil’s task is to find out pH of soils and advise the farmer which plant to grow and make suggestions how and what to do in fields where soil samples conditions are unsuitable to grow plants. Demonstrate to pupils how to conduct experiment to discover pH of different soil samples. Allow pupils to test a range of soils sample solutions by filtering soil solutions using filter paper and conical flask. Then dotting the filtrate using a glass rod onto pH paper and compare colour to pH chart and record results in a table. Write a conclusion determining which soil samples were acidic, neutral or alkali. Suggest which plants would be suitable to grow in each soil sample and advise farmer what to do to soil conditions that are unsuitable for plant growth (i.e. add lime –calcium oxide which is a base) which neutralises the acidic soil. If the soil is too alkaline then peat or manure (rotting vegetation) can be added which are acidic. This neutralises the soil to make it suitable. Pupils can then discuss their findings from the investigation. Pupils can make notes or answer questions from either Exploring science book 9 or core chemistry textbook. Worksheets are also available on the pH of soils. Extension Pupils could neutralise acidic soil solutions with limewater dropwise i.e. solutions turns green Pupils could find out about wild flowers/trees and their preferred soil type using the Internet or in textbooks and produce a leaflet to advise gardeners on the soil conditions required by different wild flowers/trees. Resources / References Pieces of sedimentary rock Different types of soils – clay, sandy and loam in glass beakers to demonstrate to pupils Class practical – acidic, alkaline and neutral soil solutions, pH paper, pH chart, glass rod, conical flask, beaker, filter paper, filter funnel Worksheets on sedimentary rock, soils and the pH of soils Core Chemistry 5.2 Getting new rock from old (sedimentary) P78 Core chemistry C3.6 Acids in soils P154-155 Exploring Science book 9 9Ga Types of soils P86-87 Homework

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Pupils could complete write up experiment for homework or research about other plants that live in acidic, alkali or neutral soils. Alternately pupils could complete worksheet on sedimentary rock and the formation of soil. Safety/Risk Assessment The soil must be uncontaminated and goggles must be worn due acidity/alkalinity of soil samples. Additional Notes It is important that pupils do not attribute acid soil to acid rain solely - rotting vegetation/manure can also cause soil to be acidic.

Associated Skills: Communication � Application of Number � Information Technology �

Working with Others � Improving own Learning � Problem Solving ��

Citizenship �

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Year 9G: Module 3 – Environmental Chemistry

Lesson 4 – The causes and effects of acid rain Learning Objectives Pupils should learn: • that rain is naturally acidic due to dissolved non-metal gases found in the atmosphere • that burning of fossil fuels releases more acidic gases which dissolve in rain water to make it more acidic • that acid rain causes buildings and certain rocks to erode, make lakes and rivers acidic • that effects of acid rain are that it kills fish and other living organisms, makes soils acidic and so kills/harms plants and trees • be aware of the ways in which emissions of acidic gases are reduced National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 2i, 3d, 3e, 3f & 3g Key Stage 2 link/Prior learning Sc3 Materials and their properties – 2f Pupils will • may know about substances that can produce acidic gases – they may identify fossil fuels • know that acid rain kills plant and animals and makes soils and lakes acidic • know that acid rain erodes buildings and rocks (taught in year 8) Suggested teaching activities Brainstorm with pupils about what is acidic rain and the causes of acidic rain. Rain is slightly acidic (pH 5.5-5.9) due to non-metal gases which dissolve in the rainwater. The causes of acid rain are mainly the burning of fossil fuels, which release more acidic gases Instruct pupils to name the gases that can cause acid rain. Carbon dioxide, sulphur dioxide and nitrogen oxides How are these gases produced? By burning fossil fuels in power stations as they contain carbon and sulphur which produces sulphur dioxide and carbon dioxide. Cars also produce carbon dioxide. The high temperature produced by sparks inside a car engine makes nitrogen and oxygen combine to form nitrogen oxide. How do we get acid rain? We get acid rain when these gases are released in large amounts into the atmosphere where they are dissolve in falling rain. How do we know we have got acid rain? The pH is below 5.6. Practical: Demonstrate the pH of an acidic gas such as sulphur dioxide by burning sulphur in air/oxygen. Placed the sulphur in a burning spoon and put it over a Bunsen burner flame. Once sulphur melts or burns and smoke is seen then place in a gas jar until the smoke is collected. Carefully remove the burning spoon and place a vaselined lid to seal the gas jar. Remove the lid briefly and add water. Place the lid back and shake the gas jar vigorously to dissolve sulphur dioxide gas into the water. An acidic

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solution (sulphuric acid) has been produced in a similar way to acid rain. Put Universal indicator solution into the gas jar and see the solution turn orange/red colour. Another practical that could be demonstrated the properties of carbon dioxide gas released is when a candle burns (the wax is made from crude oil – fossil fuel). The gases (carbon dioxide and water vapour) from candle wax burning are collected and bubbled through tubes containing blue cobalt chloride paper (turns pink when water vapour is present) and limewater (to show CO2 present) and water with UI solutions to show the weak acidic property of CO2. Demonstrate that acidic rain dissolves rocks such as limestone which contain calcium carbonate add sulphuric acid and observe the rock being eroded by chemical weathering (caused by the acid in the rain). Demonstrate the pH of rainwater samples collect at North Chadderton School – upper and lower. Instruct pupils to predict which sample would be expected to be acidic and instruct pupils to explain why. Lower school’s rainwater may be more acidic (pH below 5.5) as it is close to a busy road (more acidic gases released) but upper school situated in an area with lower levels of traffic (therefore more close to pH 5.5-5.9). Discuss with pupils about the possible ways in which pollution and acidic gas emission can be reduced. Use catalytic converter in cars, the use of sulphur precipitator at power stations and burn less fossil fuels etc. Pupils are to make notes on experiments with conclusions or teacher gives notes on acid rain. Instruct pupils to answer questions from Core chemistry textbook/Exploring science book 9. Extension Pupils could find out how emissions of acid rain are reduced using the Internet and textbooks. Pupils could write out word equations for any chemical reactions that have occurred in experiments demonstrated. Resources/References Demonstration – sulphur powder, burning spoon, safety mat, matches, splint, gas jar, limestone, sulphuric acid, Bunsen burner, UI solution/paper, pH chart, spatula, rainwater samples from upper and lower school, candle, glass funnel and tubing, test tubes filled with limewater, UI solution & water and cobalt chloride paper U-tube. Worksheet on acid rain Core chemistry 5.5 Acids in the air P84-85 Core chemistry 5.9 Why do we keep polluting the air? P92-93 Exploring science book 9: 9Gb Acid rain P89 Exploring science book 9: 9Gb The effects of acid rain P90 Exploring science book 9: 9Gb A cure for acid rain P91 Homework Complete worksheet on acid rain or find out the pH of rainwater collected at home – give pH paper and a pH chart.

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Safety/Risk Assessment Safety glasses and safety screen should be used. The fume cupboard or a well-ventilated room must be used for the burning of sulphur in oxygen. Sulphur dioxide can trigger off asthma attacks. Additional Notes Government has passed laws to reduce pollution especially acidic gases. The MOT test includes the measurement of car exhaust gases – if level is too high it will fail and cannot be driven on the roads. Associated Skills: Communication � Application of Number � Information Technology �

Working with Others � Improving own Learning � Problem Solving � Citizenship �

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Year 9G: Module 3 – Environmental Chemistry Lesson 5 – The effects of global warming Learning Objectives Pupils should learn: • that carbon dioxide gas is a greenhouse gas which is mainly caused by burning fossil fuels • that greenhouse gases released into the atmosphere cause global warming • that greenhouse gases absorb heat in the atmosphere and re-radiate it back to the surface • how effects of global warming on the world’s environment and how it can be reduced National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 3i Key Stage 2 link/Prior learning Sc3 Materials and their properties – 2g Pupils will • know that burning fossil fuels produces carbon dioxide gas • know that carbon dioxide gas is a greenhouse gas Suggested teaching activities Brainstorm with the pupils about which gases are produced when fossil fuels (coal, oil or gas) are burnt. Establish with pupils that carbon dioxide gas is one of the gases released during the burning of fossil fuels and that it commonly known as a greenhouse gas. Write ideas/answers from pupils about greenhouse gases and their effects on the world on the white board. What do we mean by the term ‘greenhouse gas’? Carbon dioxide gas traps the sun’s heat energy – the gas absorbs the heat in the atmosphere and re-radiates it back to the surface of the earth hence simulating the conditions inside a greenhouse for plants. What effect does this greenhouse gas have on the earth/world? Greenhouse gases trap the sun’s heat energy in the atmosphere (greenhouse effect) and cause global warming What is global warming and how is it effecting our environment? The main ideas about global warming is that its due to mainly large amounts of carbon dioxide gas being released into the atmosphere from burning of fossil fuels, forests, engine exhausts, factories etc., throughout the world. Scientists believe that the greenhouse gas like carbon dioxide causes the temperature rises in the atmosphere. This is effecting our environment causing weather patterns (violent storms, flooding & droughts) to change and melting ice caps at the poles causing sea levels to rise. Subsequently this has caused flooding in many areas of the world especially in many coastal areas. What can we do to stop global warming destroying our environment?

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Reduce greenhouse gases like carbon dioxide by finding alternative energy resources to fossil fuels, using our cars less, extracting carbon dioxide gas from our factories chimneys, stop cutting down and burning forests which taken in carbon dioxide gas etc., Who is responsible for global warming? (Citizenship) Most of the greenhouse gases are produced in the developed industrial countries for example the USA and in the European continent – these countries should be more responsible in reducing its greenhouse emissions by research into alternatives fuels and strict regulations. They should perhaps also help and encourage developing countries like India and Brazil to reduce their emissions and prevent forests from being cut down. Some countries are reluctant to reduce emissions due to short-term economic gains. On the whole, human activity is responsible for global warming. Pupils could be put into groups and asked to conduct one of the following tasks: a) Pupils could draw a poster or write an article for a scientific newspaper about greenhouse gases

and global warming – this should include diagrams. Data about cost to the environment, amount of gases being released etc. could be obtained from the Internet.

b) Pupils could research information on the Internet on greenhouse gases and global warming and present it in a report format with data to back up their ideas or PowerPoint presentation.

c) Role-play exercise – pupils could represent delegates from a world environment summit on global warming to put their point of view by of why they should/should not reduce greenhouse gas emissions. Pupils are to write a speech/give presentation and then undergo a Q & A session.

Pupils could represent different countries (like the USA) that are not in favour of reduction of greenhouse gases (economic gain). Brazil is a country, which does not want to reduce emissions and are burning forests in order to clear land for industrial use & economic gain. Environmentalists are worried about the effects on our environment. Scientists (some with differing views) who have made predictions about the effects of global warming on our planet in the future and have made suggestion on how we could reduce the emissions (see additional notes). Pupils may give evidence to substantiate their points of view. Alternatively pupils could copy notes from board and answer questions from the worksheets or from the exploring science book 9/core chemistry. Extension Pupils could research about other greenhouse gases and their possible sources. They could also research about the ozone layer and its effect on the environment. Pupils could also explain how use of catalytic converters help to reduce acid rain. Resources/References Worksheets – global warming Exploring Science book 9: 9Gd Global warming P94 Exploring science book 9: 9Cd A changing atmosphere P34/35 Core chemistry C3.14 Carbon dioxide and the greenhouse effect P166 Internet websites: North Chadderton/global community- has information and diagrams on greenhouse gases and global warming and other weblinks Homework Complete the worksheet on effects of global warming.

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Safety/Risk Assessment No risk Additional Notes Some scientists believe that the world temperature will not change anyway, and may even fall in the future. However we cannot be sure as there are many variables and predicting the effect of greenhouse gases is complicated. Associated Skills: Communication � Application of Number � Information Technology �

Working with Others � Improving own Learning � Problem Solving � Citizenship �

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Year 9G: Module 3 – Environmental Chemistry Lesson 6 – Monitoring pollution Learning Objectives Pupils should learn: • that there are different types of pollution that cause harm to all living things and the environment • the causes and effects of pollution i.e. burning fossil fuels, waste from factories and human consumption, oil tank disasters etc. • how pollution is monitored by scientists and the consequences of pollution (citizenship) • how air pollution compares from present and the past (smog) National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 3i Key Stage 2 link/Prior learning Sc3 Materials and their properties – 2g Pupils will • know from the previous lesson that burning fossil fuels causes air pollution releasing carbon dioxide, sulphur dioxide etc. • know that pollution causes harm to living things and the environment. Suggested teaching activities Discuss with pupils are about the different types of pollution and their causes i.e. air pollution –burning fossil fuels and fumes from cars (carbon dioxide, oxides of nitrogen), water pollution –fertiliser, pesticides, insecticides, oil slicks, acid rain – burning/releasing of acidic gases (sulphur dioxide) into the atmosphere, land pollution – chemicals and rubbish dumps, CFC’s in refrigerators etc. Instruct pupils to describe what effects these types of pollutions will have on living things and the environment. Air becomes unbreathable to animals and plants don’t survive because the conditions are not right for growth. Water is too poisonous for plants/animals to live in, algae grow more rapidly or chemicals get into food chain and water supply etc. Ask pupils how are the different types of pollution are monitored. Air quality monitoring stations, rainwater collected and pH tested around the country, lichens grow indicates clean air and low levels of sulphur dioxide gas, lake and river water tested for pesticide, insecticide, fertilisers levels for chemicals, landfill site soil tested etc. Ask pupil what could be done to reduce these types of pollution. Burn less fossil fuels and use alternative fuels that don’t release gases that cause acid rain, extract sulphur dioxide gas and other pollutants from water, air etc, use less energy to reduce amount of fuels used, walking rather than using a car/ bus etc. Pupils are to design a leaflet on the causes and effects of different types of pollution. Pupil’s leaflet should be specifically designed for year 7 pupils to be able to understand.

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Alternatively pupils could go onto the computers and research using the Internet current levels of pollution in regional areas of the UK or around the world. Pupil could use data obtained from the Internet in their leaflets. Instruct pupils to answer questions from core chemistry/exploring science book 9. Extension Pupils could research information about how specific types of pollution is reduced using the Internet or looking through the textbooks. Resources/References Worksheet on monitoring pollution. Exploring science book 9 9Gc: Measuring air pollution P92 Exploring science book 9 9Gc: Pollution in the past P93 Core chemistry 5.9 Why do we keep polluting the air P92-93 Core chemistry C3.8 Looking after the environment P158-159 Core chemistry C3.15 Waste and pollution P167 THE WEBSITES ADDRESSES BELOW NEED TO CHECKED BEFORE THE LESSON TO SEE WHETHER THEY ARE ACCESSIBLE Website: http://www.environment-agency.gov.uk/yourenv/eff/pollution/?version=1&;lang=e This describes in detail about the different types of pollution with further links http://www1.york.ac.uk/inst/sei/rapidc2.html http://www.news.bbc.co.uk/1/hi/sci/tech/1359917.stm – gives latest information about pollution (small article) http://www.aeat.co.uk/netcen/corinair/94/ - gives pie charts on levels of pollution around the Europe from 1994 http://www.aeat.co.uk/netcen/airqual/data/sitelon.html This gives data on monitored air pollution around Britain in particular London http://www.learn.co.uk/default.asap?WCI=Unit&WCU22573 Homework Complete worksheet on monitoring pollution Safety/Risk Assessment No risk Additional Notes Pupils could select diagrams and information from different WebPages and print out to be used in their leaflets. Ensure pupils only use data concerning gases such as sulphur dioxide, carbon dioxide, carbon monoxide etc, to narrow down research data. Associated Skills: Communication � Application of Number � Information Technology �

Working with Others � Improving own Learning � Problem Solving � Citizenship �

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Year 9H: Module 4 – Simple chemical reactions Lesson 1 – History and theory of burning Learning Objectives Pupils should learn: • about how scientist worked in the past and how they work today (citizenship) • about the creative thought that went into the development of scientific ideas concerning combustion • about the roles of experimentation and evidence to prove new theories • that when a substance burns its reacts with oxygen to form oxides and involves a mass increase National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 2g & 2i Key Stage 2 link/Prior learning Sc3 Materials and their properties – 2f & 2g Pupils will • know that burning substances in oxygen produces oxides taught in lessons in years 8 & 9 • know that oxygen found in air Suggested teaching activities Brain storm with pupils about burning of substance in air (oxygen) to produce oxides. Ask pupils to give another name for burning – combustion and instruct them to give examples: magnesium and oxygen to give magnesium oxide etc. Mass is conserved during this reaction. Could demonstrate to pupils the burning of different metals such as magnesium, iron filing etc in air. Discuss with pupils about how ideas of combustion arose and then discuss how scientist ideas in the past were scrutinised by society and how experimentation gave them the evidence to back their theories. Talk about how some scientist lived or had to work in other jobs in order to carry on with their experiments. (Look at additional notes) Pupils could conduct the matching scientist and their discovery card game. Pupils are to research on the Internet or on CD ROMs – Put into the search engines the name of the scientist, their scientific theories or the scientist’s nationality scientist. Early ideas by the Greeks on combustion Boyle’s experiment of heating tin in a sealed flask The phlogiston theory Lavoisier’s experiment The discovery of oxygen by priestly Combustion Pupils could design a poster/leaflet on the history of combustion/on one particular scientist’s struggles to prove their theory on combustion. The spread: spotlight science 27b: A burning Tale covers this in story-cartoon form. Pictures of relevant scientist and questions sheet based on spread 27b are available.

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Instruct pupils to answer questions from Core Chemistry textbook/Exploring science book 9. Extension Pupils could produce a PowerPoint presentation on the history of combustion. Resources/References Magnesium strip, iron filings etc, safety mat, matches, splint, tongs, Bunsen burner Worksheet spotlight science 27b: A burning Tale – related questions sheet and pictures of related such as Democritus, Boyle, Lavoisier and Priestley. Core chemisry3.5: Metals reacting with oxygen P50-51 Core chemistry C2.5: Elements reacting with oxygen P125-126 Core chemistry C2.2: Chemical reactions P120 Exploring Science book 9: CRb Chemistry at home P109 Exploring Science book 9: 9Hd Burning ideas P104-105 Exploring Science book 9: 9Ha Energetic reactions P96 Spotlight science 9: 27b A burning tale P30-31 Websites from the Internet: http://www.lexcie.zetnet.co.uk/virginia-lavoisier.htm Homework Complete poster/leaflet on scientist and the history of burning Safety/Risk Assessment Safety glasses and safety screen should be used if demonstrating burning of magnesium or other metals. Additional Notes Pupils often have the misconception that substances decrease in mass when they burn. This exercise relates practical evidence of substances gaining mass when heated to various ideas such as phlogiston theory. With the discovery of oxygen it was realised that air was not a single substance and it was this gas which reacts when a substance burns. Associated Skills: Communication � Application of Number � Information Technology �

Working with Others � Improving own Learning � Problem Solving � Citizenship �

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Year 9H: Module 4 – Simple chemical reactions Lesson 2 – The combustion of magnesium Learning objectives Pupils should learn: • that magnesium burns to form magnesium oxide • that the mass (Grams or Kg) increases as an oxygen atom is added to the magnesium atom to form magnesium oxide • that when a compound is formed it has a fixed composition • that law of conservation of mass (dealing with chemical change and mass) • be able to conduct the burning of magnesium experiment National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 2a & 2g Sc 1 Scientific enquiry - 2f, 2k & 2l Key Stage 2 link/Prior learning Sc3 Materials and their properties – 2f & 2g Pupils will • know the theories of burning • know that magnesium burning in oxygen produces magnesium oxide from the previous lesson Suggested teaching activities Teacher demonstration or class practical dealing with chemical change and mass: Demonstrate to pupils to how they will investigate the effects on mass when burning magnesium ribbon (use spotlight science textbook P34/35) Pupils are to pool results after experiment conducted. Pupils are to make a prediction on the mass to be made before carrying out experiment.

Practical: Different lengths of magnesium are to be given to pupils. Pupils are to weigh empty crucibles and lid and reweigh with magnesium loosely coiled in the crucible. Crucible is then heated gently at first then more strongly, with the lid being lifted on and off regularly to allow oxygen into the crucible. Pupils need to subtract the difference in weight before and after the experiment. This is to find out the difference in mass to prove that the mass increase is due to the oxygen being combined to the magnesium atom to form magnesium oxide (note: mass of oxygen could not be measured initially because it is a gas). Discuss with pupils the law of conservation of mass. Mass cannot be lost or gained during a chemical reaction is known as the Law of conservation of mass. Mention that the magnesium oxide has a fixed composition because magnesium oxide contains one of atom of oxygen for each atom of magnesium. Ask pupils to give examples where mass would be conserved in everyday situations (e.g. rusting of iron nail, candle wax burning etc.) – chemical change and mass

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Results are often too unreliable to plot on graph therefore better to use results given in spotlight science 27d: It’s a Fix. To plot graph of mass of magnesium oxide against mass of magnesium to give a straight line to show mass added is proportional to mass of magnesium used. Extension Also carry out 27d: making magnesium chloride from magnesium involves plotting a similar graph. Q3 P35 spotlight science. Resources/References 15 crucibles and lids, 15 strips of magnesium of varying lengths, top-balance, tongs, heating apparatus, pipe clay triangle, calculators Worksheets – burning of magnesium Core chemistry C2.10: chemical change and mass P135 Exploring science book 9: 9Hc A matter of mass P102-103 Spotlight science Year 9: 27d: It’s a fix with corresponding worksheets Homework Write up the experiment including a result table, pooled graph and conclusion. Complete the worksheet on the burning magnesium. Safety/Risk Assessment Safety glasses must be worn and care should be taken handling hot crucible and lid, using tongs. Ensure that pupils don’t look directly at the magnesium ribbon burning – a strong white glow. Additional Notes This experiment can be unreliable, especially if too many fumes are allowed to escape – the lid has to be carefully lifted using the tongs to allow oxygen into the heated crucible with magnesium.

Associated Skills: Communication � Application of Number � Information Technology � Working with Others � Improving own Learning � Problem Solving �

Citizenship �

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Year 9H: Module 4 – Simple chemical reactions Lesson 3 – Fuels and their energy release Learning objectives Pupils should learn: • that heat given out to the surroundings when some chemicals react together i.e. burning fuels in oxygen • that these types of reaction are called exothermic reaction • how to carry out an experiment to discover the amounts of heat energy in different fuels • that some of the energy is transferred to the environment i.e. air and apparatus used to heat substances • to know other examples of exothermic reactions i.e. neutralisation, hydrating anhydrous copper sulphate crystals, producing a salt from a reactive metal and acid etc. National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 2c, 3i Key Stage 2 link/Prior learning Sc3 Materials and their properties – 2g, 2f Pupils will • know that burning fuels in oxygen is called combustion • know that burning fuels produces heat Suggested teaching activities Brainstorm with pupils why we burn fuels and instruct them to give examples? To produce energy in the form of heat. Types of fuels – (fossil fuels) coal, oil and natural gas (alcohol maybe suggested as it can be used in Brazil as fuel to power cars). Instruct pupils to either plan or conduct the experiment after the teacher demonstration on: How much heat energy is released from different fuels (natural gas, candle wax and alcohol)? Practical: Pupils are to heat up 100cm3 of water in a beaker for 5 minutes using the 3 different types of fuels. They will use a Bunsen burner for natural gas, a candle and alcohol burner. They must monitor the temperature rise every minute and ensure the same fuels are burnt at the same height from the beaker. Pupils must record initial temperature of water and ensure they record the results in a table. Graphs can be drawn of the temperature rises and final conclusion can be done. Is all the energy released by burning a fuel transferred to the water? No – some of the energy is transferred to the environment i.e. surrounding air and apparatus etc. Some of the energy is transferred to other types of energy i.e. light, sound. Explain to pupils that the burning of fuels is an example of an exothermic reaction and demonstrate/give other examples of exothermic reactions i.e. neutralisation, hydrating anhydrous copper sulphate crystals in a glass dish, producing a salt from a reactive metal and acid (Mg & HCl in a test tube) etc. Instruct pupils to answer questions from Core chemistry textbook/Exploring science book 9.

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Extension Pupils could experiment/research further will other types of fuels and their energy release i.e. oil burners or research using the Internet (renewable energy sources). Pupils could also discuss other types of chemical reactions that release energy when they react. Resources/References Worksheet on exothermic reactions Core chemistry C3.8: Looking after the environment P58-159 Exploring science book 9: CPb Energy in chemistry P122-123 Exploring science book 9: 9Ha Energetic reactions P96-97 Spotlight science 9: 34f Finding the energy P142-143 Bunsen burner, a candle, alcohol burner, beaker, thermometer, water, tripod, gauze, safety mat, measuring cylinder Homework Complete write up of experiment. Safety/Risk Assessment Safety glasses should be worn and caution must taken with burning flammable substance like alcohol. Additional Notes The candle wax (hydrocarbon – made from crude oil) burning will produce soot (carbon) on the beaker. Pupils need to use non-flammable materials to prop up their fuels to the correct height or alternatively they could use a clamp. The tip of the flame for each burning fuel must just touch the beaker and the gas tap can be adjusted to reduce Bunsen burner flame. Another fuel that could be investigated is wood shavings on a tin lid. Associated Skills: Communication � Application of Number � Information Technology �

Working with Others � Improving own Learning � Problem Solving � Citizenship �

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Year 9H: Module 4 – Simple chemical reactions

Lesson 4 – Displacement reactions and their energy release Pupils should learn: • that a more reactive metal will displace a less reactive metal from its salt solution • that this type of reaction is called a displacement reaction • how to determine which metals will displace other metals from their solutions using a reactivity series • that some displacement reactions are exothermic i.e. release energy in the form of heat • to conduct an experiment to show the amount of heat energy released by monitoring the temperature in different solutions. National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 3c, 3b, 3h Key Stage 2 link/Prior learning Sc3 Materials and their properties – 2c, 2f Pupils will • know what a displacement reaction is and the reactivity series – taught in the module patterns of reactivity • know what exothermic reaction is – from previous lesson Suggested teaching activities Brainstorm with pupils about displacement reactions and the reactivity series (taught in module 2). Ask pupils what else occurs during a displacement reaction besides the displacing of a less reactive metal and replacement with a more reactive metal. Energy is released in the form of heat – the reaction is also exothermic, colour change, bubbles, other physical properties etc. Teacher could demonstrate by adding iron filling to copper (II) sulphate solution in a conical flask, noting its temperature rise, the red precipitate of copper and the change in colour of solution from blue to pale green. Practical: Pupils could use conduct their own experiment using different metals and solutions. Put 25 cm3 of copper sulphate solution in a polystyrene cup (placed in a beaker for stability) and add powdered magnesium metal. Record initial temperature of solution and add one spatula at a time and record the temperature rise. Pupils could repeat experiment with another metal such as zinc powder or iron filings. The results could then be plotted on a graph and word equations could be written for the displacement reactions. Pupils could then discuss the temperature rise in their conclusion, relating the reactivity of the metal added to the copper sulphate solutions. Instruct pupils to answer questions from core chemistry textbook/exploring science book 9. Extension Pupils could investigate further the temperature rises of other metals and different salt solutions.

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Resources/References Worksheet on exothermic and displacement reactions Core chemistry 3.7: Which metals push hardest? P54-55 Core chemistry C2.7: Displacement reactions P130-131 Exploring science book 9: CPb Energy in chemistry P120-121 Exploring science book 9: 9Fc Knowing your place P82-83 Spotlight science 9: 34f Finding the energy P142-143 Iron filling, copper (II) sulphate solution, thermometer, polystyrene cup, beaker, measuring cylinder, zinc powder, magnesium powder, graph paper, rulers Homework Pupils could research about other exothermic reactions (fireworks, explosive, acid and metal, burning of carbon in oxygen, how sport heat packs work etc.) or complete worksheet on exothermic reactions. Safety/Risk Assessment Safety glasses should be worn. Additional Notes Every reaction needs some energy to get going but in exothermic reactions the energy needed to activate the reaction is about room temperature. The products of the reaction have less energy than the reactants. The difference in energy is given out as heat therefore the temperature rises. Associated Skills: Communication � Application of Number � Information Technology �

Working with Others � Improving own Learning � Problem Solving � Citizenship �

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Year 9H: Module 4 – Simple chemical reactions

Lesson 5 – Solubility I Learning objectives Pupils should learn: • that a saturated solution is one in which no more solute will dissolve (at that temperature) • that the mass of a substance that can dissolve in a certain volume of solvent (at that temperature) is called the solubility of the substance • how to measure and calculate the solubility of a substance by observing how much mass will dissolve in its solvent before saturation National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 2a, 2b Key Stage 2 link/Prior learning Sc3 Materials and their properties – 2a, 2b, 2c, 2d, 3b Pupils will • know that a solution is made from a solute and a solvent taught in year 7 and discussed in previous chemistry lessons Suggested teaching activities Brainstorm will pupils about the what the terms solution, solvent, solute, solubility and saturated solution. Explain and demonstrate the appearance of a saturated solution (some undissolved solid at the bottom of the beaker or in evaporation at the point of crystallisation) using sugar in 100cm3 of sugar at room temperature. Demonstrate and explain to pupils that 100cm3 of water posses a mass about 100g. Pupils may need to be shown how to weigh the mass of their substance using the balance. Practical: Instruct pupils are to conduct an experiment to find out the solubility of salt at room temperature (20°C). (Which salt is most soluble?) Pupils could find the solubility of sodium chloride (salt) Pupils could weigh out on a balance about 10-15g of a salt. Then pupils are to dissolve as much of the salt as possible by stirring with a glass rod in 50 cm3 of water. At the point when the solution becomes saturated with the substance they can reweigh the remaining amount of substance and calculate the total mass of substance dissolved and hence the solubility of that substance at room temperature. Alternatively less able pupils could just count the number of spatulas added to the water stirring until the point of saturation and then discuss the number of spatulas of mass dissolved in a certain volume of water. Pupils could then discuss the solubility of the different substances at room temperature (salt and sugar).

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Instruct pupils to answer questions from core chemistry textbook/exploring science book 9 or worksheet. Extension Pupils could plan an experiment to investigate which factors effect the solubility of substance like copper sulphate. Pupils could also research into the solubility of gases in water/liquids. Resources/References Worksheets on solubility Core chemistry C1.7 making pure white sugar P106-107 Spotlight science 9 32g: Dissolving P118-119 Exploring science book 9: CRc Kitchen chemistry P110-111 Sugar, sodium chloride (salt) Beakers, balances, spatulas, water, measuring cylinders, glass rod Homework Complete worksheet on solubility Safety/Risk Assessment Safety glasses should be worn and care taken not to get copper sulphate in contact with skin (irritant). Additional Notes Ensure pupils record mass before and after adding salt to the solvent. Pupils must know the mass of container in which substance place in and stir regularly. Associated Skills: Communication � Application of Number � Information Technology �

Working with Others � Improving own Learning � Problem Solving � Citizenship �

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Year 9H: Module 4 – Simple chemical reactions

Lesson 6 – Solubility II Learning objectives Pupils should learn: • that how to measure the solubility of a substance by observing how much mass will dissolve in its solvent at different temperatures • that the solubility of a substance can vary due to temperature • that there are differences in solubility of solutes in different solvents • to be able to plot, read and draw values from a solubility curve. • be aware that the solubility of gases may vary in water at different temperatures National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 2a, 2b Key Stage 2 link/Prior learning Sc3 Materials and their properties –2a, 2b, 2c, 2d, 3b Pupils will • know about solutions, solvents, solutes, saturated solutions and solubility of a substance taught in the previous lesson • may know that the solubility of a substance could vary with temperature taught in previous lesson/year7 Suggested teaching activities Revise with pupils the previous work done on solubility of substances. Brainstorm with pupils about which factors effect the solubility of a substance. Temperature, surface area, solvent etc., Practical: Pupils could plan an experiment on the solubility of sugar in 50g of water at range of temperatures from 50oC. Pupils could measure the amount of substance added to the water. The mass of the substance will be weighed at the beginning of the experiment using a balance (the mass of the container should be weighed separately). Pupils are to heat up water to chosen temperature and dissolve as much as the sugar as possible and stirring with a glass rod until solution is saturated. Then remaining mass of the substance will be then re-weighed and the solubility of salt in 50g water calculated. Alternatively teacher demonstration can be done using copper sulphate dissolved in 50g of water in a beaker at 50 oC. Weighing of copper sulphate (approx. from 25g) must be done after saturation and solubility calculated. Pupils are to discuss the effects of temperature on solubility (it increases solubility of most substances). Pupils to look at worksheet on solubility of different substances at different temperature. Instruct pupils to answer questions from Core chemistry textbook/Exploring science book 9. Extension

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Pupils could conduct/discuss at the solubility of other substances at other temperatures. Resources/References Worksheets on solubility Sugar, copper sulphate, thermometers, beakers, spatulas, glass rod, balance, Bunsen burner, tripod, safety mat, gauze, matches, measuring cylinders Core chemistry C1.7 Making pure white sugar P106-107 Core chemistry 1.4: Mixing solids and liquids P16-17 Spotlight science 9 32g: Dissolving P118-119 Exploring science book 9: CRc Kitchen chemistry P111 Homework Complete worksheet on solubility of substances at different temperatures Safety/Risk Assessment Safety glasses are to be worn during heat experiment. Additional Notes Pupils should work in large groups (3-4), as large amounts of mass of the substance will be dissolved in water at higher temperatures.

Associated Skills: Communication � Application of Number � Information Technology �

Working with Others � Improving own Learning � Problem Solving � Citizenship �