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Chemistry Rotation 1

Each chemistry module has a total of six lessons assigned to them, giving a total of twelve lessons for the chemistry rotation. This is then followed by two lessons of Sc 1 and one lesson for the two module test.

Module 1: 9E – Metals and their compounds

Lessons Title

1 The properties of metals2 The corrosion of metals3 The chemical reactions between metals and acids4 The chemical reactions between metal carbonates and acids5 The chemical reactions between metal oxides and acids6 Chemical reactions and their word equations

Module 2: 9F – Patterns of reactivity

Lessons Title

1 The reactivity of metals with water2 The reactivity of metals with acids3 Displacement reactions 4 The reactivity series5 The conservation of mass I6 The conservation of mass II

Scientific Investigation 1

7 Sc 1 lesson8 Sc 1 lesson9 Module 1 & 2 test

Year 9E: Module 1 – Reactions of metals and their compounds

Lesson 1 – Metals and their properties

Learning objectives

Pupils should learn:

that metals are good conductors of heat and electricity that most non-metals are poor conductors of heat and electricity that metals are usually shiny, malleable, ductile, strong, have high densities, sonorous and have high melting points – with the exception of mercury which is liquid at room temperature that non-metals are usually dull, brittle, poor conductors of heat and electricity (exception carbon or graphite) and have low melting points (exception of diamond - carbon) about the range of metals and their symbols as well as their uses to use the properties of an element to classify it as a metal or non-metal

National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 1a, 1c & 1d

Key Stage 2 link/Prior learning

Sc3 Materials and their properties – 1a, 1b & 1c

Pupils will know the names of some metals and non-metals and their chemical symbols know some of the properties of metals and non-metals know some uses of metals

Suggested teaching activities

Starter Activity Bromine in well-sealed test tubes and mercury in a sealed transparent boiling tube.

Demonstrate a circuit with a low voltage power pack and a bulb. Instruct pupils to put elements in a table labelled non-metals and metals.

Core Activity Ask pupils to suggest the reasons why they put the different elements into the non-metal/metal

column. To help pupils ask questions such as: Are metals good conductors of heat/electricity? Are non-metals all gases? Where do we get metals from (iron, gold, lead and silver)? What are they used for? Pupils could use data books.

Instruct pupils to write the list of properties of metal/non-metals in exercise books or copy from the board/worksheet.

Demonstrate using a periodic table to show where the metals (LHS) and non-metals (RHS) are situated.

Instruct pupils to colour on their sheets the position of metals and non-metals on the periodic table. They could also highlight the two liquid elements – mercury and bromine. Ensure pupils identify graphite/carbon as a non-metallic conductor of electricity.

Pupils answer questions from core chemistry/exploring science book 9 or complete worksheets.

Plenary Using a Badger key stage 3 science, copymaster for starter 48 as revision. Write on the board

or get OHP of the list of properties of metals and non-metals

Extension

Ask different groups to explore different questions and to produce a fact sheet about a particular element or property. Help pupils to use these to make a comparison of non-metals and metals and to explain what makes them useful.

Resources/References

Samples of elements: magnesium ribbon, iron nails, lumps of sulphur, graphite rods, zinc foil, lead foil, gas jar of chlorine, gas jar of oxygen, gas jar of nitrogen, gas jar of bromine, mercury. Low voltage power pack, connecting leads and bulb.Data books with information about elements

OHPOHP transparency with copymaster for starter 48 (Badger key stage 3 science starters)Core chemistry 3.1: Looking at metals P42-43Core chemistry 3.2: Non-metals P44-45Core chemistry 3.3: Where do we find non-metals? P46-47Core chemistry 3.4 Elements of THAR P48-49Core chemistry C1.2 Metals and non-metals P96-97Information about elements: CD-ROM’s available: The chemistry set, elements and materials.Exploring Science book 9: Spot the difference P64-65, P107- chemistry everywhereExploring Science worksheets: 9Ea/1, ‘different properties’, 9Ea/2, ‘properties fact sheet’, 9Ea/3, ‘what do we use metals for?’ 9Ea/4, ‘metals with memory’Spotlight science Year 9: 27a P28: The Periodic tableSEN worksheet: C6b, ‘metal detecting’, ‘spot the difference’, C6c, ‘heavy metal’

Homework

Pupils should learn the chemical symbols of twenty elements i.e. C, S, Zn, Mg, O, N, Cl, Br, Fe, H, Pb, etc.,Complete worksheets on metal/non-metals.

Safety/Risk Assessment

Chlorine and bromine should be disposed of in the fume cupboard. Pupils must not handle mercury.Hazard cards for mercury, bromine and chlorine should be issued.

Additional Notes

Pupils often confuse non-metals with non-metallic materials such as plastic and wood. It is helpful to restrict this activity to elements. Pupils should contrast the conductivity of different metals and non-metals. Mention alloys being made up from a mixture metals and non-metals e.g. steel is made from a mixture of iron and carbon. Metals are have high densities (explain the word density) and are sonorous. Not all metals are magnetic, metals which are magnetic are iron (strongly), nickel and cobalt.

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


Lesson 2 – The corrosion of metals

Learning objectives


that many metals are affected by oxygen in air and water that different metals are affected in different ways that some metals are soft and can be cut that iron/steel objects need air (oxygen) and water to rust (corrode) and that rust is a hydrated form of iron oxide that most ways of preventing rusting is by putting some kind of barrier between the iron and the water such as painting, greasing, coating with another metal or plastic.

National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 1e, 1f & 3e


Sc3 Materials and their properties – 2f

Pupils will know that many metals react with oxygen to form oxides know that iron object rust in everyday life know how to prevent rusting of objects i.e. painting/greasing of parts of bicycle


Starter Activity Show pupils a range of objects e.g. copper and nickel coins, a tarnished silver cup, and a

relatively new rusty iron cup/object. Ask pupils to describe what has happened to each and explain the possible causes.

Elicit ideas about the effects of air/water and different effects on different metals – corrosion of these metals (see additional notes). Emphasise the use of the two terms - corrosion (all metals including iron) and rusting (only used for in the corrosion of iron).

Core Activity Teacher demonstration/class practical to determine the conditions needed for iron to rust.

To determine the conditions needed for rusting – 3 tubes are set up containing an iron nail in each. The tubes are set up as follows:

Tube 1: Tap water added (both air add water present) – control experimentTube 2: A few pellets of anhydrous calcium chloride to absorb moisture (water vapour in air)Tube 3: Water freshly boiled for a couple of minutes (to remove air) added with a layer of oil to prevent re-entry of airDue to time constraints, instruct technician to set up the experiment a few days before lesson as to show pupils the results in the same lesson.

Sc 1 opportunity when conducting the experiment, with pupils focusing on their prediction, fair testing, results and conclusion

Instruct pupils to write up experiment (which should include a prediction with explanations) with an empty table of results, which be filled in next lesson, or if teacher demonstration show them the results of a previous rusting experimental set-up.

Show one reactive metal such as lithium – cut and ask pupils to explain why the outside surface becomes dull/tarnished and the inside surface is shiny when first exposed. Link with rough order reactivity with these metals and gold being unreactive. Point out the unusual nature of sodium, potassium and lithium as metals – soft density, low melting point. Ask why these metals are stored in paraffin oil (very reactive with moisture and oxygen in the air).

Discuss and then instruct pupils to list the methods are carried out to prevent rusting. Then ask them to give examples in everyday situations that they are used to prevent rusting (painting cars, oiling lawnmower blades/machinery, chromium plated handlebars, coating with a more reactive metal, galvanised roofs – coated with zinc, tin plated food cans, etc.,)

Instruct pupils to answer questions from Exploring Science book 9 or core chemistry textbook. Worksheets on rusting could also be done.

Plenary Activity

Pupils to carry out activity from Badger key stage 3 science starters’ copymaster for starter 54, ‘Which conditions cause iron to rust?’

Extension

Pupils could design an experiment to show that iron reacts with oxygen during rusting – give pupils apparatus list ask them to design experiment. Help pupils deduce that water level risen 20cm3 the volume of air used up is 20cm3 therefore the percentage of air used up is 20/100x =20%, which corresponds to the percentage of oxygen in the air.

Teacher demonstration to show that iron reacts with oxygen during rusting (ask technician to set up already). Explain to pupils how experiment is set up and that oxygen is being investigated in its involvement in rusting. To show that oxygen is the gas used up in rusting, set up a small bag of moist iron filings supported in an inverted measuring cylinder, containing 100cm3 of air, over a trough of water. Record the water level initially and then again in the following lesson.


For the demonstration order equipment a few days in advance for the before and after of the Rusting experiment – iron nails, test tubes, tap water, anhydrous calcium chloride, oil, boiled water, test tube rack and a small measuring cylinder.Core chemistry 5.8: A problem with metals P90-91Core chemistry C3.4: A corroding metals P150-151Exploring Science book 9: P108 Crb, ‘Chemistry at home’Exploring Science 2 worksheets: C7e/1, ‘rusting 1’, C7e/2, ‘rusting 2’, C7e/3, ‘Protecting iron1’ and C7e/4, ‘protecting iron 2’Badger key stage 3 science starters’ copymaster for starter 54, ‘Which conditions cause iron to rust?’Samples of rusted/corroded objects – coins, cups etc.Lithium, scalpel, tile, tweezers, paper towels, safety screen, small trough of water Oxygen experiment - moist iron filings, measuring cylinder, trough and water.Other worksheets – on rusting and corrosion

Homework

Complete worksheet on corrosion/rusting.


Lithium are corrosive and highly flammable and small pieces the size of rice grains should be used. Safety glasses and safety screen should be used.

Additional Notes

Not only oxygen in the air reacts with metals when they corrode. E.g. copper goes green because it reacts with carbon dioxide to form copper carbonate, silver tarnishes because it reacts with sulphur compounds such as SO2. The exercise only gives a rough indication of the relative reactivity of different metals.Its is very difficult to remove all the air from water when boiling so the iron does rust slightly in this tube.Both rusting experiments need to be left for a few days.Rust is a hydrated iron (III) oxide so needing water as well as oxygen to form. This reaction is an oxidation reaction. The word equation can be given as:

Iron + oxygen iron oxide

Extension:4Fe + 3O2 2Fe2O3



Lesson 3 – The chemical reactions between metals and acids

Learning objectives Pupils should learn:

that some metals react with dilute acids to form salts and release hydrogen gas to carry out the test for hydrogen gas that metals do not all react in the same way to represent the reactions of metals with dilute acids by word equations to identify patterns between metals and dilute acids to use patterns to make predictions about other reactionsExtension: be able to write symbol equations to represent chemical reactions

National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 3a & 1f


Sc3 Materials and their properties 2f

Pupils will Know a metal with an acid in year 7/8 and tested for hydrogen gas but will not have named the products of the reactions


Starter Activity Demonstrate with a metal (Calcium –one grain required) and dilute sulphuric acid reacting and

test for hydrogen. Before demonstration, pupils are to predict and describe their observation of the chemical reaction. Pupils could also discuss the products of the reaction. (Sc1 Planning & Observation).

Core Activity Pupils to predict which metals will react with the acid and conduct their own experiments as

follows. , Exploring Science worksheet 9Fb/2, ‘Reactions of metals with acids 2’may help.

Class practical: Pupils could carry out reactions of hydrochloric acid with magnesium, zinc, iron and copper. Note and compare the vigour of the reactions.

Pupils to add 5 different metals to 2cm depth of 1M hydrochloric acid. Pupils to observe reactions and test for hydrogen gas. Pupils to add 1 strip (2cm length) of magnesium, 1 small piece of zinc foil/ granules, 1 small spatula measure of iron filings and 1 small piece of copper foil (1cm square) to the remaining tubes.

Pupils are instructed to trap the gas for varying lengths of time before holding a lit splint at the top of the tube (time varies from a few seconds for calcium for several minutes for iron. Note: copper does not react at all).

Instruct pupils to record their observations systematically in a table and prompt them by using a series of questions: What is similar about the reactions? Is a gas is being made? How do you know and what is it? Are there colour changes? Does the tube get hot or cold?

Teacher could combine all the solutions formed from one of the reactions e.g. magnesium chloride and leave the solution to evaporate till next lesson to obtain the salt.

Pupils are to write up experiment and write word equations for all the above reactions conducted.

Discuss with pupils that when an acid reacts with a metal then the salt name depends upon the acid used i.e. sulphuric acid gives salts that contain sulphates, nitric acid gives salts that contain nitrates and hydrochloric acid gives salts that contain chlorides. Discuss the general word equation for the reaction.

Metal + Acid Metal salt + Hydrogen gas Put onto the board other combinations for pupils to predict the products. Instruct pupils to answer questions from Exploring Science book 9/core chemistry textbook.

Plenary Activity Pupils to carry out activity from Badger key stage 3 science starters’ copymaster for starter 56,

‘Let’s test reactivity of metals with acids’

Extension

Extension: Pupils to write symbol equations for the chemical reaction carried out.Core chemistry textbook work/worksheets.


Test tubes, test tubes rack, boiling tubes, splint, matches & Bunsen burner.Calcium granules for teacher, pieces of magnesium ribbon (2cm long).Pieces of zinc and copper (1 cm square), iron filings, 6 bottle of 1M of hydrochloric acid (2 bottles for each bench), beakers to dispose of residues, large crystallising dish to put one resultant solution into.Exploring Science book 9: P66-67Exploring Science worksheets: 9Fb/1, ‘Reactions of metals with acids 1’, 9Fb/2, ‘Reactions of metals with acids 2’, 9Fb/3, ‘Reactions of metals with acids 3’Badger key stage 3 science starters’ copymaster for starter 56, ‘Let’s test reactivity of metals with acids’Core chemistry 4.6: How do metals react with acids? P68-69Core chemistry C2.6: More about metals and acids P128-129 (extension)Spotlight science Year 9: P34b: Making salts P134-135Other worksheets on the reactions of metals with acids

Homework

Complete worksheet on the reactivity of metals with acids.


Pupils should be shown the hazard sign corrosive and be aware that any spillage should be mopped up after rinsing with plenty of water. Safety glasses are essential. The reaction with calcium and magnesium are very fast exothermic- care should be taken.Iron tends to give off some toxic hydrogen sulphide as well.Note that any reaction that still has undissolved solid at the end should be disposed into a container at the end of the experiment and not put into the sink.

Additional Notes

Calcium and magnesium react very quickly- a matter of seconds. Zinc starts slowly then speeds up and hydrogen should be detected after a couple of minutes. Iron reacts very slowly and may not give a positive test after several minutes. Teacher could demonstrate by carefully warming the mixture to speed up the reaction before testing for the gas. When leaving resultant solution to evaporate, make sure excess metal has been added so that the acid is not evaporated. If sulphuric acid is used, very little reaction will be seen with calcium as insoluble calcium sulphate forms, which precipitates and stops the reaction.If nitric acid is used, hydrogen is not detected. Instead oxides of nitrogen result.



Lesson 4 - The chemical reactions between metal carbonates and acids

Learning objectives


that acids react with metal carbonates producing a salt, carbon dioxide and water know that carbon dioxide turns lime water milky know how to test for carbon dioxide gas to write word equations for this type of reaction apply their knowledge to the reaction of acid rain with carbonate rocks such as chalk, limestone and marble

National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 3e, 3g, 3h & 1f

Key Stage 2 link/Prior learning Sc3 Materials and their properties – 2f& 2g

Pupils will know the test for carbon dioxide gas taught during year 7/8 – respiration experiments. know acid rain’s effect on rocks taught in year 8.


* (The teacher may want to go through results of rusting experiment set up from the previous lesson)

Demonstrate a reaction of powdered calcium carbonate with hydrochloric acid, showing test for carbon dioxide gas by pipetting into limewater (turns cloudy white). Relate this reaction with carbonate rocks such as chalk limestone and marble. Mention that the tube gets hot during this chemical reaction. Ask pupils what effect acid rain has on the objects such as statues made from carbonate rock- marble?

Class practical – ask pupils to investigate what happens when a range of carbonates react with other acids such as sulphuric acid, hydrochloric acid and nitric acid. Each bench to be supplied with carbonates such as those of copper, sodium, zinc and magnesium. Each pair of pupils is given the task of reacting, each carbonate with any of the acids provided. In each case the gas evolved is pippetted into a tube of fresh limewater.

Instruct pupils to record their observations systematically in a table and prompt them by using a series of questions: What is similar about the reactions? Is a gas is being made? How do you know and what is it? Are there colour changes? Does the tube get hot or cold?

Instruct pupils to write up experiment in neat.Give pupils the names of a variety of metal carbonates and acids, with the names of products and instruct them to work out word equations:

Metal carbonate + Acid Metal salt + water + carbon dioxideMention that the acid used in the reaction is important i.e. sulphuric acid gives salt that contain sulphates, nitric acid gives salts that contain nitrates etc.Pupils could answer questions from Core Chemistry textbook.

Extension

Give pupils the formulae of a variety of metal carbonates and their corresponding chlorides, sulphates and nitrates and instruct them to work out products. Help them to construct symbol equations.


Bottles of dilute nitric, hydrochloric and sulphuric acids and limewater are put on each benchSamples of 4 carbonates, including copper carbonate to be placed on each benchTest tubes – enough for 5 per groupTeat pipettes for each groupSamples of chalk, limestone and marble

Worksheets on metal carbonates and acidsCore chemistry: 4.5: Using neutralisation reactions: P66/67Core chemistry 5.6: Things we can do with limestone: P86/87Cards with names of metal carbonates: acids: salts: carbon dioxide and water on.Spotlight science Year 9: 34b: Making salts: P134/135

Homework

Worksheet on metal carbonates and acids OR Research the effects of acid rain on buildings/statues/metallic objects/caves etc., made from limestone, marble etc. (carbonates) and its cost – look for news/science reports about specific landmarks/buildings globally and what was done to eradicate/reduce the problem.ORComplete worksheet debating about acid rain effects. - Citizenship


All acids are corrosive and safety glasses must be wornCarbonates may be irritants – see specific hazcardsSpillage to be rinsed with plenty of water

Additional Notes

In the activities in this unit, it may helpful to emphasise that nitrate and sulphate are groups of atoms, which stay together in this reaction.


Year 9E: Module 1 – Reactions of Metals and their compounds

Lesson 5 –The chemical reactions between metal oxides and acids

Learning objectives


that acids react with metal oxides producing a salt and water to represent the reaction in terms of a word equation to know how to use filtering apparatus and the reasons behind its use to make a crystalline sample of a salt

National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 1f, 1h & 3e


Sc3 Materials and their properties – 2f, 3b, 3c3 & 3d

Pupils will know that some metal oxides can form alkaline solutions in water know how to filter and evaporate solutions as carried out/observed in year 7/8 and at KS 2


Introduce the class practical the reaction between a metal oxide and an acid. (Hand out worksheets on the practical of making copper sulphate crystals). Mention to the pupils that metal oxides are alkali substance that don’t dissolve in water (called a base).

Demonstrate the practical of gently heating a metal oxide (copper oxide) and a dilute sulphuric acid.Take this reaction further by instructing pupils to repeat the experiment using 25cm3 of warm dilute sulphuric acid in a 100cm3 beaker. Then adding copper oxide little by little and stirring gently until the excess oxide does not dissolve. Then some filter off the black oxide and partially evaporated the remaining blue solution (if time) and/or leave to evaporate slowly in a crystallising dish until next lesson.

Help pupils to construct word equation and by using formula to identify the other product. Ask pupils why this reaction did not make bubbles.

Word equation: Metal oxide + acid metal salt + water

Give pupils the names of other salts and ask them to suggest which acid and metal oxide would be needed to make them.When salts are crystallised then ask pupils to look at different obtained sample to see the different sizes of crystals obtained relate this to speed of the reaction (large crystals).Pupils could answer questions from Core Chemistry textbook.

Extension

Some pupils might investigate what happens to the pH of the acid when the metal oxide is added could provide an opportunity for data logging using ICT. Pupils could practise writing symbol equations for this reaction.


Samples of copper (II) oxide on each bench, 2 bottles of dilute sulphuric acid on each bench, spatulas, stirring rods, 100cm3 beakers, filter funnels, filter paper, evaporating dishes, crystallising dishes, Bunsen burners, tripods, safety mats, gauzes, matches, splint, safety goggles

Worksheets on salts Core chemistry 4.6: How do metals react with acids? P68/67Core chemistry 4.7: Salt and salts: P70/71Core chemistry C2.6: Metals reacting with acids: P128/129Spotlight science Year 9: 34b: Making salts P134-135.

Homework

Pupils could be asked to write up the experiment.Complete worksheet on making salts


Do not use nickel oxide, which is toxic and a grade 1 carcinogen.Pupils should be warned to boil the acid as soon as it begins to bubble the heat should be removed.Acids are corrosive and safety glasses are essential. Appropriate hazcards for oxide should be consulted. 0.4Moldm-3 acid is suitable.

Additional Notes

The reaction is very slow if no warming is done first. Ensure pupils add excess oxide so that the acid is not evaporated. Nitrates should not be made as they decompose on heating.


Year 9F: Module 2 – Patterns of reactivity

Lesson 1 – The reactivity of metals with water

Learning objectives


that some metals react more readily with water than others the order of reactivity series of metals (such as potassium, sodium, lithium, calcium) with water the word equations associated with the reactions between metals and water that hydrogen gas is released in some cases when metals react with water and that reactions are exothermic How the reactivity series can used to predict chemical reactions

National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 3a, 3b & 3c



Pupils will know the names of some metals that do/do not react with water from previous lessons and work from Year 7 & 8 may know about the reactivity series from previous lessons in Year 9


Teacher demonstration: the reactivity of lithium, sodium, potassium, calcium, magnesium, aluminium, zinc and copper with water. Recap from previous lesson as shown below but drop pieces of metal into the trough full of water.

Show the reactivity of metals such as potassium, sodium, lithium, calcium, magnesium, aluminium, zinc and copper with cold water – cut and ask pupils to explain why the outside surface becomes dull/tarnished and the inside surface is shiny when first exposed. Link with rough order reactivity with these metals and gold being unreactive. Point out the unusual nature of sodium, potassium and lithium as metals – soft density, low melting point. Ask pupils why these metals are stored in paraffin oil. Could put UI solutions to show metals have reacted with water i.e. turns from green to purple in some cases with Group I metals - potassium.

Pupils to write out about the metals and their observations (reactivity, floating, colour flame given off, Hydrogen gas being given off etc.,) when they were dropped into water. Ask pupils to put metals into order of reactivity.

Set up magnesium strip in cold water under a filter funnel with boiling tube on the top in a large beaker. Add UI solution to water above the filter funnel and leave for a week (monitor colour change throughout the week changing from green to purple and the magnesium tarnishing and dissolving).

Ask pupils to predict how fast the reaction would be magnesium strip with the cold water and in steam. Also ask pupils where hydrogen and carbon (non-metals) would be in this reactivity series as some metals displace hydrogen from water therefore these metals are more reactive than hydrogen.

Instruct pupils to complete worksheet and answer questions from core chemistry textbook.

Extension

Instruct pupils to write word equations for the reaction of metals with water. They could also write symbol equations for their reactions.


Potassium, sodium, lithium, calcium, magnesium, aluminium, zinc, scalpel, tile, tweezers, paper towels, safety screen, boiling tube, filter funnel, Universal indicator solution & water

Worksheets – on reactivity of metalsCore chemistry 3.6: Metals reacting with water P52/53Core chemistry: C2.17: More about the reactivity series P142/143

Homework

Instruct pupils to find out about the extraction of metals such as zinc, iron, and lead, with carbon.Pupils to complete worksheet on reactivity of metals.


Potassium, sodium and lithium are corrosive and highly flammable and small pieces the size of rice grains should be used. Safety glasses and safety screen should be used.UI solution is flammable – keep away from flames.

Additional Notes

Only add very small pieces of lithium, sodium and potassium metals – hydrogen gas given off in each case, most metals that react with water produce metal hydroxides which are alkaline and give a purple colour with UI solution.

Metal + Water Metal hydroxide + Hydrogen gasNa (s) + H2O (l) NaOH (aq) + H2 (g)

Reactivity series

Potassium – most reactiveSodiumCalciumAluminiumCARBON – metals above cannot be extracted from their ores by heating with carbon/ metals below can be extracted using carbonZincIronLeadHYDROGEN – metals below hydrogen will not displace it from water, steam or dilute acidsCopperSilverGold – least reactive



Lesson 2 – The reactivity of metals with acids

Learning objectives


that some metals react with dilute acids to form salts and release hydrogen gas the hydrogen gas test that not all metals behave in the same way and identify patterns where possible to represent chemical reactions between metals and acids, metals and water and metals with general word equations about the reactivity series of metals with acids to make a comparison with reactivity series of metals with water to use patterns to make predictions about other reactions

National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 1F & 3a



Pupils will know the about some metals reacting with acids and others not from the previous lesson may know of the reactivity series of metals with acids know the reactivity series of metals with water


Brainstorm with pupils about the reactivity series of metals with water, general word equations and gas produced (hydrogen) put on board. Ask pupils to predict the reactions of metals with dilute acid (Recapping from previous lesson)Conduct a teacher demonstration or class practical for the reaction between calcium, magnesium, aluminium, zinc, iron and copper and dilute acid (hydrochloric acid) and test for hydrogen for each one. Instruct pupils to write up observations in a table.Ask pupils to explain why potassium, sodium and lithium with acid not conducted in the laboratory (too dangerous! – extremely reactive). Discuss with pupils about reactivity series of metals with acids along side that of water and ask pupils for similarities and any differences between them. Write the points on the board.Ask about why aluminium foil does not react when it high on the reactivity series (thin oxide layer).Instruct pupils to write word equations for the reaction for selection of metals and acids on the board (include nitric acid and sulphuric acid). Mention that a metal salt is produced along with the hydrogen gas.Pupils write out reactive series of metals with acid stating most reactive and the least reactive.Pupils could answer questions from core chemistry textbook and complete worksheets on reactions.

Extension

Pupils could write symbol equations for all reactions and complete worksheets.


Metals such as magnesium, calcium, iron, zinc, copper, splint, matches, Bunsen burner, safety mat, dilute hydrochloric acid, test tubes, test tube rack, boiling tube

Worksheets – on reactivity series of metals with oxygen, water and acidsCore chemistry 4.6: How do metals react with acids? P68/69Core chemistry C2.6: More about metals and acids P128/129Core chemistry 3.5: Metals reacting with oxygen P50/51Core chemistry C2.5: Elements reacting with oxygen P126/127Core chemistry 3.6: Metals reacting with water P52/53Core chemistry 3.8: Which metals react best? P56/57

Spotlight science Year 9: 34b: Making salts P134/135

Homework

Complete worksheet on the reactivity series.Pupils could research and explain what are displacement reactions and give an example including a word equation for next lesson.


See previous lesson on metals and acids. The reaction of calcium and magnesium are very fast and very exothermic – care should be taken and safety goggles worn.

Additional Notes

Potassium, sodium, lithium are very reactive therefore no reactions with acids and oxygen is carried out. Calcium is reactive with acid and water but very reactive with oxygen therefore should be not carried out. Aluminium is reactive with water, acid and oxygen but due to its immediate reaction with oxygen and forming a thin oxide layer it does not appear to react with the above reagents in the laboratory. This should be pointed out to pupils.



Lesson 3 – Displacement reactions

Learning objectives


about the displacement reactions that take place between metals and solutions of salts of other metals how metal react with the oxides of other metals and the products made that some energy is given out during displacement reaction i.e. exothermic reaction how the reactivity series of metals can be used to make predictions about other reactions that displacement reaction can be useful and to give examples of their uses in everyday life situations




Pupils will know about the reactivity series of metals from previous lessons may have some knowledge about displacement reactions (from the possible homework set)


(Ask pupils about their research on displacement reactions that was set for homework) - optionalDemonstrate to pupils the class practical on displacement reactions. Pupils provided with a spotting tile given the following: Magnesium, iron, copper, zinc and solutions of the metal salts e.g. sulphates of magnesium, zinc, iron (II) and copper. Instruct pupils to test metals and combinations of metals and metal salts to find out if there is a reaction, recording their results in a table. Instruct pupils to identify a pattern in their results and derive a reactivity series of metals from the results.

Write up experiment on board and draw table of results with a list of metals in a column heading and metal sulphate solutions row heading. Instruct pupils to conduct experiment noting their observations for any changes/reactions and complete table with a cross or a tick. Instruct pupils not to conduct experiment with the same metal and its metal sulphate solution and put cross initially.

Discuss results and use an analogy or model to explain the displacement of the less reactive metal by a more reactive one. (Drawings circles to represent the atoms (metals) and molecules (sulphates, nitrates & chlorides) maybe useful in a word equation)

Ask pupils to predict whether the other reactions will occur as pupils to give word equations for each reaction.

Show using an analogy e.g. ‘pull of a metal on sulphate and word or symbol) equations that whether there is a reaction or not depends on the metal in the salt and not the acid from which the salt is derived.

Teacher could further demonstrate by adding iron filling to copper (II) sulphate solution, noting it temperature rise, the red precipitate of copper and the change in colour of solution from blue to pale green

ORAdd a drop of silver nitrate solution to copper wire and use a binocular camera attached to TV screen to show displacement of silver crystals on top of the wire.

Pupils to answer questions from core chemistry textbook or complete worksheet on displacement reactions.

Extension

Ask pupils to write symbol equations for all reactions that occurred. Instruct pupil to research about the Thermit reaction between aluminium and iron oxide and to explain the use of the exothermic nature of the reaction in welding.


0.4moldm- class set of beakers with the solutions of sulphates of magnesium, zinc, iron (II) and copper, thermometer, beakerIron filings, small pieces of zinc, copper and magnesium, spotting tiles, droppers,

Silver nitrate solution and copper wire, binocular camera, TV, dropper, container

Worksheets – on displacement reactionsCore chemistry 3.7: Which metals push the hardest P54/55Core chemistry C2.7: Displacement reactions P130/131

Homework

Complete worksheet on displacement reactions and to find out about any uses of displacement reactions in industry.


0.4moldm-3 or 0.1moldm-3 solutions of salts can be usedAppropriate hazcards should be consultedSafety glasses should be worn

Additional Notes

For the displacement reaction, using very small quantities in spotting tile works well. In some cases e.g. with magnesium, the reaction may between the water and the metal instead.This activity provides an opportunity to use ICT to reorder tables of results.Although analogies e.g. pull of the metal are not strictly correct, they may be helpful to pupils in establishing principles about displacement.



Lesson 4 – The reactivity series

Learning objectives


how an activity series can help to make sense of the reactions of metals how an activity series can be used to make predictions that sometimes the data doesn’t enable firm predictions/conclusion to be made to relate the occurrence, extraction and use of metals to there position in the activity series to identify what information is needed and use different texts as sources to structure paragraphs to develop points, using evidence and additional facts




Pupils will know how metals react with oxygen, water and acids know about displacement reactions involving metals and their solutions


Ask pupils to predict the reaction of metals with oxygen and demonstrate only magnesium strip (hold using tongs), zinc granules (burning spoon), iron filings (sprinkle), and lead (burning spoon) and copper strip (hold using tongs)Discuss with pupils if prediction correct and list the reactivity series of metals with oxygen.Discuss general trend (see worksheet and previous lesson plan) with pupils and recap general word equations for metals with oxygen and water.

Pupils could write up the summary table listing the reactivity of metals with oxygen, water and acids or be given a worksheet with details missing for them to fill in.

Tell pupils the position of an unknown metal and ask them to predict its reaction. Give pupils information about the reactions of metals not already in the series and ask them to predict where they might come.

Then discuss with pupils (using white board) any difficulties in coming to a decision.

Discuss with pupils about extraction of metals using the reactivity series (aluminium is reactive therefore harder to extract than iron and why it wasn’t used as early as iron) and non-metals such as carbon. Recap displacement reactions.

Instruct pupils to answer questions from the core chemistry textbook or complete worksheets on reactivity series.

Extension

Ask pupils where non-metals like hydrogen and carbon may be in the reactivity series and explain their positions. Also instruct pupils to research about the extraction of metals such as aluminium, copper, iron and sodium etc in textbooks or using ICT internet/CD ROM’s.


Bunsen burner, matches, splint, burning spoon, metals such as zinc, copper, lead, magnesium, iron filings, tongs

CD ROMs available: The chemistry set, Elements, Materials, The periodic tableWorksheets – Reactivity series/extraction of metalsInformation about copper can be found on the Internet e.g. at www.copper.org.Core chemistry 5.7: Getting metals from rocks P88/89Core chemistry C3.3: Getting metals out of rocks P1478/149Core chemistry C3.10: Smelting metals P162/163

Homework

Ask pupils to use secondary sources (ICT Internet or textbooks) together with their own knowledge of metals to find the answers to a series of questions of varying difficulty e.g.

Why is sodium not used for cutlery?Why is a light metal like magnesium not used for car bodies?Why has so much gold jewellery survived from ancient civilisations? Why was bronze (an alloy of copper and tin) used before iron?Aluminium is much more abundant than iron, so why wasn’t it used until the beginning of the 21st century?Which metals are found naturally?What are the sources of magnesium? Why is it not found naturally?How are metals recycled?

Ask pupils to present their findings and help them to organise the points to produce an information leaflet linking metal’s reactivity to their uses (including when they were first used).


Safety goggles and safety screen need in the reaction of metals and oxygen.Instruct pupils not to directly stare at the magnesium strip burning in oxygen.Zinc and lead will glow and then melt in the burning spoon.Use fume cupboard when burning zinc and lead oxide should be formed.

Additional Notes

Pupils should be encouraged not to look into too much detail at extraction processes but to identify the key points about the method e.g. using electricity, smelting with carbon etc.



Lesson 5 – The conservation of mass I

Learning objectives


that when a substance burns it reacts with oxygen to from oxides that when a physical change of state occurs for a substance, mass is conserved i.e. an ice cube melting (solid to a liquid) that when salt is dissolved in water the can be recovered through evaporation and its mass does not change that mass is conserved in the formation of solutions i.e. salt solution – final mass should be equal to the addition of the mass of the salt and the mass of the water.

National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 2a & 2g



Pupils will know the difference between a physical and chemical change covered in year 8 know that a ice cube with change state from a solid to a liquid when it melts


Ask pupils about the difference between physical change and chemical change and to give examples.Teacher demonstration or class practical – dealing with physical change and mass:Conservation of mass practical - add 10grams of salt to beaker of water. Stir until all the salt dissolves. Ask pupils how to get back the salt? (Evaporate the water by heating the salt solution)Ask pupils to predict what the mass of the salt will be after evaporation and why they think this. Weigh the salt after evaporation and it should weight 10 grams. When something stays the same we say that it is conserved. The mass of the salt was conserved through two physical changes – this is called the conservation of mass.

Dissolve weigh out 100g of water and 5-10 grams of salt (or any other amounts). Then stir until all the salt has dissolved and weigh the solution. It total weight should be 110 grams (if 10g of salt added to 100g of water). The conservation of mass occurs in the formation of solutions.

Do substances alter in mass when they change state? Get an ice cube and weigh it on a balance and leave it to melt on a dish on the balance. The mass of the ice cube remains the same even when it has melted. Conservation of mass applies to all physical changes of state.

Ask pupils to give other examples where mass would be conserved in everyday situations (butter melting, cup of coffee being made etc) – Physical change and mass.

Pupils to write up the results from experiments and explanations (include the law of conservation of mass in relation to changes of physical state and formation of solutions).

Pupils to answer questions from worksheet and core chemistry textbook.

Extension

Pupils could research about Lavoisier experiment proving that mass doesn’t change when it burns (Spotlight science P30/31).


Balances, spatulas, beakers, glass rods, salt, ice cube and dish, water, measuring cylinders, freezing containers

Worksheets – on the conservation of massCore chemistry C2.9: Physical change and mass P134

Spotlight science Year 9: 27b: A burning tale P30/31

Homework

Complete worksheet on conservation of mass/physical changes.


Safety goggles to be worn.Broken glassware must be thrown in the broken glass bin.

Additional Notes

Emphasise the difference between physical and chemical change and relate this to mass.Chemical change is irreversible and new products are made (compounds)- the different types are oxidation, reduction, decomposition, exothermic, endothermic, neutralisation and displacement reactions. Physical change is reversible and that no new products are made (mixtures) – relating to changes of state.



Lesson 6 – The conservation of mass II

Learning objectives


that law of conservation of mass (dealing with chemical change and mass) that a when chemical reaction occurs i.e. displacement reaction between magnesium ribbon and copper sulphate solution that its mass does not change that the mass (Grams or Kg) increases in the case of magnesium burning in oxygen to form magnesium oxide due to oxygen being a gas (mass is conserved as a gas cannot be weighed) that when a compound is formed it has a fixed composition

National curriculum reference: Key Stage 3 Sc3 Materials and their properties – 2a & 2g


Sc3 Materials and their properties – 2f & 2g

Pupils will know about displacement reactions know that magnesium burning in oxygen produces magnesium oxide from the previous lesson know about the conservation of mass during a physical change


Teacher demonstration or class practical dealing with chemical change and mass:Demonstrate to pupils the displacement reaction between magnesium ribbon and copper sulphate solution. Ask pupils what the they expect to observe during the reaction (solution goes from blue to colourless and the temperature rises)Pupils to make a prediction on the mass to be made before carrying out experiment.

Practical:Place a conical flask, cotton wool and thermometer on a balance and record its mass. Then zero the balance. Put about 100cm3 of blue copper sulphate solution into the conical flask. Take and record the temperature of the solution. Then dangle a piece of magnesium ribbon (4g) using a cotton thread inside the conical flask above the solution and record their total mass. Drop the magnesium into the solution and observe how the solution change from a blue to colourless and the temperature increases but the mass remains the same. The changes proved that a chemical reaction had occurred and that the mass was conserved.Instruct pupils to write up experiment, which should include a table of results and put a word equation for the displacement reaction.

Discuss with pupils the law of conservation of mass.Mass cannot be lost or gained during a chemical reaction or a physical change is known as the Law of conservation of mass.

Mention that the magnesium sulphate has a fixed composition because it is a compound.Ask pupils to give examples where mass would be conserved in everyday situations (e.g. rusting of iron nail, candle wax burning, burning magnesium etc.) – chemical change and mass

Pupils are to answer question from core chemistry textbook or complete worksheets.

Extension

Pupils could investigate other chemical reactions where mass is conserved i.e. magnesium burning in oxygen. Ask pupils why there seems to be an increase in mass – due to oxygen atom attached to magnesium atom.


Cotton thread, balance, thermometer, cotton wool, magnesium ribbon, copper sulphate solution, conical flask, measuring cylinder

Worksheets – chemical change and massCore chemistry C2.10: chemical change and mass P135

Spotlight science Year 9: 27d: It’s a fix with corresponding worksheets

Homework

Complete write up the experiment including a results table and conclusion orComplete worksheet on the chemical changes/conservation of mass


Safety glasses must be worn. Wash off with water immediately if copper sulphate solution is spilt on hands or desk.

Additional Notes

Note: the mass increases in the case of magnesium burning in oxygen to form magnesium oxide due to oxygen being a gas (mass is conserved as a gas cannot be weighed).



Lesson 5 – The conservation of mass II

Learning objectives


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


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


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 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 lid being lifted on and off regularly to stop fumes escaping but allow oxygen in.

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

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.


15 crucibles and lids, 15 strips of magnesium of varying lengths, top-balance, tongs, heating apparatus, pipe clay triangle, calculators

Worksheets – burning of magnesiumCore chemistry C2.10: chemical change and mass P135

Spotlight science Year 9: 27d: It’s a fix with corresponding worksheets

Homework

Write up the experiment including a results table, pooled graph and conclusion.Complete worksheet on the burning magnesium.


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.


Documents

Rotation 1 - Webucate.org – Resources for Teachers and ... · Web viewHelp pupils deduce that water level risen 20cm3 the volume of air used up is 20cm3 therefore the percentage