Describe what happens when a liquid will not dissolve any more of a solid and use correctly the terms: solubility, saturated solution. State what happens to mass in a physical change. Securing Describe how factors affect how much of a substance dissolves. Describe how we know that different solutes have different solubilities. Exceeding Plan a fair test to discover how different factors affect the solubility of a substance. Exploring: Does it dissolve? Students test what happens when different substances are stirred into a beaker of tap water. Provide a range of soluble and insoluble substances for testing. Explaining: Snowstorm in a test tube Demonstrate the change of solubility with temperature using lead iodide. Ask students to explain what they see and why it happens. Plenary: Thinking skills Plus, Interesting: Teabags should be made bigger, and have bigger holes. (Possible answers: Plus – more water would get into the bag so the soluble substances in the tea would dissolve out faster; Minus – the pieces of tea would need to be bigger so they stay in the bag; Interesting – Would this change the flavour of the tea? In May 2013 a food company in Australia unveiled a teabag with a mass of 151 kg – enough for 100 000 cups of tea. substances for testing. Demonstrate the change of solubility with temperature lead iodide. Ask students to explain what they see and why it happens. Lesson 7Ec: Evaporation Learning objectives Exemplar teaching activities Differentiation Resources skills Practical skills Developing Describe what happens during evaporating. State what happens at a material's boiling point. Securing Starter: Recovering solids from solution Stir a spoonful of a soluble salt into a small beaker of water until the solid has fully dissolved. Then ask: How could we get the solid back out Exploring: Making salt from rock salt Give this practical context by providing Resources from 7Ec Exploring Science. n/a Students obtain samples of pure salt from rock salt, using the techniques of
Describe the use of universal indicator and pH meters to determine the pH of a solution. Describe solutions as being more or less acidic/alkaline by comparing their pHs. Exceeding Use information indicator colour changes to design different indicators for different purposes. Explaining: pH probe and universal indicator Have prepared a set of test tubes with solutions of different pHs. Add indicator to each and stand a white card behind the rack so students can see the colours easily. Ask them to refer to pH charts to work out the pH of the contents of each tube, and then use a pH probe and datalogger to measure the pH. Plenary: Thinking skills Odd One Out: 1, 8, 14. (Possible answers: 1 is the only pH number that is an acid; 8 is the only number that represents a less hazardous/dangerous/powerful substance.) each and stand a white card behind the rack so students can see the colours easily. Ask them to refer to pH charts to work out the pH of the contents of each tube, and then use a pH probe and datalogger to measure the pH. Lesson 7Fd: Neutralisation Learning objectives Exemplar teaching activities Differentiation Resources Maths skills Practical skills Developing Recall that react with alkalis and this is called neutralisation. Explain how chemical reactions are different to physical changes. Interpret a word equation to identify the products and reactants in a chemical reaction. Recall some applications of neutralisation (changing the pH of soils). Supply missing reactants or products to complete a word equation. Securing Starter: Making the spill safe 'Spill' some acid into a wide shallow container. Use indicator (liquid or paper) to show that the liquid is acidic. 'Cancel' the acidity by adding sodium hydroxide solution. Show that any remaining liquid is now neutral. Exploring: Changing the pH Students investigate how pH changes when an acid is diluted and when it is neutralised. Universal indicator or pH meters can be used. Students can plot a graph of their results. Explaining: Following neutralisation Prepare graphs and challenge students to state what must have happened to cause any changes in pH shown. Resources from 7Fd Exploring Science. Reading and plotting line graphs. Students investigate how pH changes when an acid is diluted and when it is neutralised. Universal indicator or pH meters can be used. Use a pH probe and a
metres to millimetres, micrometres and nanometres. Explaining: Investigating Brownian motions Set up a demonstration of Brownian motion using a smoke cell. Plenary: Thinking about theories Odd One Out: the Sun and Moon circle the Earth, Rajesh will go shopping tomorrow, all things can exist in one of three states, shadows are formed when light cannot pass through something. (Possible answers: ‘the Sun and Moon circle the Earth’ has been disproved; ‘Rajesh …’ is a prediction whereas the others are theories.) Lesson 7Gd: Diffusion Learning objectives Exemplar teaching activities Differentiation Resources skills Practical skills Developing Describe diffusion as the movement of one substance through another without any external mixing. Recall some everyday examples of diffusion. Make a prediction about diffusion. Securing Explain how diffusion occurs in terms of movement of particles. Explain why the of diffusion in gases is faster than in liquids. Recognise examples of diffusion causing problems. Starter: Diffusion Place a container of a strong-smelling substance (ethanol, perfume or in the room just before the students enter. Some students may comment on the smell, and others may notice that the smell has not reached all areas of the room. Discuss the reasons for this and introduce the term ‘diffusion’. Exploring: Diffusion of hydrogen chloride and ammonia n/a Resources from 7Gd Exploring Science. n/a Demonstrate the ‘traditional’ experiment investigating the diffusion of hydrogen chloride and ammonia The demonstration should be carried out in a fume cupboard.
Explain the ways in which gas pressure can be increased (more particles introduced into a container, container is made smaller, gas is heated). Describe what a vacuum is. Explain some of the effects of air pressure (e.g. using a straw, collapsing can). Exceeding Explain how barometers work. Explaining: Talking pressure Demonstrate and discuss some experiments that can be explained with reference to air/gas pressures. After each experiment the students should be asked to write a description of what happens and an explanation using gas pressures. Plenary: Thinking about pressure Consider All Possibilities: a car tyre bursts. (Possible answers: there is a puncture; the pressure in the tyre was too high; the tyre got too hot.) experiment the students should be asked to write a description of what happens and an explanation using gas pressures. Lesson 7Ha: The air we breathe Learning objectives Exemplar teaching activities Differentiation Resources Maths skills Practical skills Developing Describe the difference between a mixture and pure substance. Recall the of the most important gases that are mixed together in air. State that all matter is made up of tiny particles called atoms. Explain the differences between elements, compounds and mixtures (with reference to elements being substances that cannot be broken down into anything simpler by chemical means). Explain the difference between an atom and a molecule. Interpret particle models of mixtures, atoms, molecules, elements and compounds. Securing Starter: purity Students draw up a on a piece of paper with two columns headed ‘pure’ and ‘mixture’/‘impure’. They define the terms and list as many words or phrases connected with the headings as possible. Discuss the meaning of the terms when referring to matter. Exploring: Displaying data Tell students about a series of investigations that could be done about air and ask them to sketch the type of chart or graph that they would draw for each. Students should be encouraged to add labels Explaining: Elements, compounds and mixtures Extend this by asking students to pick appropriate terms to describe models as you display them (e.g. pure, mixture, atoms, molecules, element and compound). Resources from 7Ha Exploring Science. The use of: tables; line graphs; scatter graphs; pie charts; and bar charts. n/a
Represent atoms, molecules of elements and simple compounds using a model. Exceeding Write simple chemical formulae from molecular structures. whether a chemical is an element or not, and a metal or a non-metal. Students then swap their keys with other groups to be ‘road-tested’. Lesson 7He: Chemical reactions Learning objectives Exemplar teaching activities Differentiation Resources Maths skills Practical skills Developing Recall examples of chemical reactions in everyday life. Recall some observations that indicate a chemical reaction. Identify the products and reactants using a word equation. Supply missing reactants or products to complete a word equation. Identify thermal decomposition reactions. Securing Model simple reactions using word equations. Recall examples of energy being used to start a chemical reaction or keep it going. Describe what happens during thermal decomposition of a metal carbonate. Name compounds that contain two elements plus oxygen. Exceeding Apply knowledge of thermal decomposition in carbonates to other compounds. Starter: Different changes Demonstrate the difference between a chemical and a physical change and how one is easier to reverse than the other, by burning a match and bending a match (use long matches, and do not break them). Then demonstrate folding a piece of cotton or wool fabric and burning it. Ask students to describe the difference between the changes. Exploring: Household reactions Provide simple instruction cards for students to carry out a set of experiments using mainly household chemicals. Students decide whether there is no reaction, a reversible or an irreversible change and state if a change is physical or chemical and explain why. Explaining: Word equations 2 Use some of the simpler chemical reactions to introduce the terms for reactants and products and explain how reactions can be described by using word equations. Exploring: Household reactions Students should be able to categorise the chemical reactions – needing or not needing energy to start them off, reversible or not, undergo physical and chemical change or just chemical change, etc. Resources from 7He Exploring Science. n/a Students carry out a set of experiments using mainly household chemicals.
Plenary: Thinking about chemical reactions Odd One Out: calcium oxide, calcium carbonate, carbon dioxide. (Possible answers: carbon dioxide is the only gas; calcium carbonate as it is the reactant- the others are products; calcium oxide, as it does not contain carbon.) Lesson 8Eb: Oxidation Learning objectives Exemplar teaching activities Differentiation Resources skills Practical skills Developing what happens to mass in a chemical reaction. State the meaning of: oxidation. Describe the reactions of metals with oxygen. Identify and explain the products formed by the oxidation of metals. Securing Explain the change in mass seen in reactions. Compare and contrast the oxygen and phlogiston theories for combustion. Exceeding Evaluate the evidence used to displace the phlogiston theory of combustion. Model simple reactions using symbol equations. Starter: Combustion concept map 1 the word ‘combustion’ in the middle of the board and ask students to suggest related words and identify how they should be linked to produce a concept map. Encourage students to suggest definitions for any related terms. Exploring: Losing mass Students use a tea light or spirit burner to investigate any change in mass after burning. They should explain any change using what they have learnt about the combustion of hydrocarbons. Explaining: Conservation of mass demonstration Demonstrate the oxidation of a metal (e.g. copper) in a closed system to show students that there is no change in mass during an oxidation reaction. n/a Resources from 8Eb Exploring Science. n/a Students use a tea or spirit burner to investigate any change in mass after burning.
Working Scientifically Identify variables that need to be controlled in a given experiment. Plan ways in which to control a simple control variable. Explain the need for a fair test. Plan ways in which to control more than one variable. Justify the choice of control variables. oxygen is excluded from the fire; the heat is taken from the fuel by reducing its temperature with water; the fuel is used up.) Lesson 8Ed: Air pollution Learning objectives Exemplar teaching activities Differentiation Resources Maths skills Practical skills Developing Recall examples of non-metal oxide pollutants caused by burning fossil fuels and their impurities. Describe the reactions of non-metals with oxygen. Securing Explain the products formed by the complete and incomplete combustion of hydrocarbons. Explain the problems caused by incomplete combustion. Explain how sulfur dioxide and nitrogen oxides are produced in some combustion reactions. Explain how sulfur dioxide and nitrogen oxides help to cause acid rain. Explain how neutralisation can be used to reduce pollution from fossil fuel combustion. Explain how vehicle catalytic converters work (to reduce pollution from fossil fuel combustion). Starter: Water cycle pollution Students sketch the water cycle and label it to show where the changes of state of water take place. They then consider how air pollution leads to ground and water pollution as a result of the water cycle, and annotate their diagrams to show this. Exploring: Measuring pollution Students use sticky cards to compare particulate (e.g. soot) pollution in different areas. They should formulate one or more hypotheses about the locations that will have the highest levels of particulate pollution then test these. Explaining: Catalytic converter Outline how a catalytic converter Students could draw molecular diagrams to show the reactions that take place inside the catalytic converter. Exploring: Measuring pollution Students can find out about different sampling techniques. Resources from 8Ed Exploring Science. Calculating means. Students use sticky to compare particulate (e.g. soot) pollution in different areas.
Demonstrate, using a double-pan balance, how one large nail can be balanced in mass by several small nails. Relate this to how we compare the masses of atoms of different elements. Plenary: Thinking about Dalton’s atomic model Consider All Possibilities: A substance contains the atoms of three different elements. (Possible answers: it is a mixture of three separate elements; a mixture of one element and one compound; a single compound.) Lesson 8Fb: Chemical properties Learning objectives Exemplar teaching activities Differentiation Resources Maths skills Practical skills Developing Explain how chemical reactions are different from physical changes. Explain the difference between physical and chemical properties of a substance. Use observations to decide whether a chemical reaction has taken place. Model simple chemical reactions using word equations. Use a simple (Dalton’s) atomic model to describe a compound. Securing Model more complex chemical reactions using word equations. Describe how atoms are rearranged in chemical reactions. Starter: of reactions Students work in pairs to list chemical reactions they have seen in the laboratory or in everyday life. Each pair should then choose one reaction to illustrate using a labelled diagram or drawing. Display these on a ‘gallery wall’. Exploring: Modelling reactions Students use polystyrene and cocktail sticks to model the reaction between carbon and oxygen to form carbon dioxide. Explaining: Using observations of change Demonstrate what happens when mercury oxide is heated and beads of mercury metal are seen to form on the Exploring: Modelling reactions Students add explanatory notes, using the five points from Dalton’s atomic theory. Resources from 8Fb Exploring Science. n/a Students use polystyrene balls and cocktail sticks to model the reaction between carbon and oxygen to form carbon dioxide.
Compare the physical and chemical properties of metal and non-metal oxides. Recall there is usually a regular gradation in chemical properties as you go down a group. Use data to identify trends in chemical properties within a group. Identify a pattern of reactivity in the reaction between some alkali metals and water and use this to predict the reactivity of other alkali metals. Exceeding State that atoms can be joined up to make molecules or giant lattice structures. Describe the difference between molecules and giant lattice structures. Explaining: Different structures Show students the structure of different oxides representing molecular and lattice structures using molecular models, e.g., sulfur dioxide molecules and a magnesium oxide lattice. Discuss the differences between the structures and link these differences with the melting points of the oxides. Plenary: Thinking about trends in chemical properties Consider All Possibilities: When a mixture of an element and oxygen is heated and is added the pH remains 7. (Possible answers: the element does not react with oxygen; the element is hydrogen and the product formed is water; the element forms an oxide that is insoluble in water.) Lesson 8Gb: Corrosion Learning objectives Exemplar teaching activities Differentiation Resources Maths skills Practical skills Developing Describe the corrosion of metals by reactions with oxygen. Identify and explain the products formed by the oxidation of metals. State the meaning of: rusting. Recall ways in which iron can be prevented from rusting. Recall some reactions that happen slowly and some that happen quickly. Starter: Describing substances Arrange a number of different objects made of different materials, in ‘stations’, around the room. Working in pairs, ask students to list adjectives that describe the appearance or properties of each of the objects. Exploring: Investigating rusting Explaining: Symbol equations for combustion Equations for the reactions of zinc and copper will follow a similar format, while those for sodium oxide (Na2O) and iron oxide Resources from 8Gb Exploring Science. n/a Students set up an experiment to investigate the conditions required for iron to rust.
Relate the uses of different elements to their chemical properties. Securing simple oxidation reactions using word equations. Explain how barrier methods protect iron from rust. Identify the products and reactants using a symbol equation. Exceeding Model simple reactions using balanced symbol equations. Ask students to set up an experiment to investigate the conditions required for iron to rust. Explaining: Symbol equations for combustion Give students the formulae of some metal oxides and ask them to construct balanced symbol equations for the reactions that have occurred, e.g. the balanced equation for magnesium is: 2Mg + O2 → 2MgO. Work through the format with the students. Plenary: Thinking about corrosion Odd One Out: copper, magnesium, gold. (Possible answers: gold is the only metal which does not corrode/ react with oxygen; magnesium is the only one that burns in air; copper is the only one that could be used for water pipes; magnesium is the only silver-coloured metal.) (Fe2O3) are more challenging. Aluminium oxide has a similar formula to iron oxide. Lesson 8Gc: Metals and water Learning objectives Exemplar teaching activities Differentiation Resources skills Practical skills Developing Describe the reactions of different metals with water. Describe the gas test for hydrogen. Relate the uses of different elements to chemical properties. Securing Starter: What reacts? Give students a list of 10 metals, including the metals used in building (i.e. aluminium, calcium, copper, gold, iron, magnesium, potassium, silver, sodium and zinc). Ask them to the metals up into two groups according to whether they are predicted to react with water or not. n/a Resources from 8Gc Exploring Science. n/a Students investigate the reactions of calcium, copper and magnesium with their reactivity and the gas produced.
Developing Describe what happens during changes of State what happens at a material’s melting, freezing and boiling point. what is meant by: pure. State the meaning of: alloy. Explain why metals are often alloyed with other elements. Securing that a pure material has a fixed melting point and boiling point. Describe how impurities alter melting, freezing and boiling points. Identify a pure substance from its melting or boiling point. Use models to explain why converting pure metals into alloys often increases the strength of the product. Exceeding Describe some ways in which purity is stated. Plot and interpret graphs of melting point or boiling point for mixtures of varying compositions. Starter: Alloy demonstration Demonstrate melting solder, allowing the molten metal to drip into a tin lid. If possible, demonstrate how solder is used to join copper pipes or wires together. Exploring: Researching alloys Ask students to use and/or the Internet to find out about alloys. Explaining: Harder alloys Explain how the introduction of different atoms into a metal structure to make an alloy can make it harder and more rigid. Illustrate the idea by using marbles in a tray. Plenary: Thinking about pure metals and alloys Plus, Minus, Interesting: Alloys should have the same properties as the pure metal. (Possible answers: Plus – properties of metals would be consistent and well known; Minus – there would be no point in making alloys as you could not improve their properties; Interesting – would metals have so many uses?) Exploring: Researching alloys Students could compare the properties of the alloy with the properties of the component metals and add information about how the purity of alloys is stated. Resources from 8Ge Exploring Science. n/a Demonstrate melting solder, allowing the molten metal to drip into a tin lid. If possible, demonstrate solder is used to join copper pipes or wires together. Lesson 8Ha: Rocks and their uses Learning objectives Exemplar teaching activities Differentiation Resources Maths skills Practical skills Developing Recall what earthquakes and volcanoes are. Starter: Rocks brainstorm Ask students to jot down as many facts about rocks and soils as they can. Students can then try to n/a Resources from 8Ha Exploring Science. n/a Students investigate the permeability of rocks by finding
Recall some examples of common ceramics (e.g. pottery, glass). State the meaning of: ceramic. Explain how the properties of ceramics make them useful. Securing Justify the use of a ceramic material for a given application. Explain why crystal size depends on the speed of cooling. Explain how the properties of a substance depend on the bonding and arrangement of atoms (in terms of strength and number of bonds only). Exceeding Explain why modifications in a certain ceramic or glass manufacture can change its properties (e.g. lead crystal). (Involves consideration of type and arrangement of atoms.) china, pottery, porcelain, coloured glass, clear glass, poly(ethene), poly(styrene), PVC, rubber, concrete, glass fibre, paper, plywood, etc.). Ask them to split the objects up into an appropriate number of different groups, based on the materials that the objects are made of. Exploring: Crystals Students place a drop of molten salol (phenyl salicylate) onto warmed and chilled microscope slides. When the salol has solidified, students examine the samples using a hand lens or microscope. Explaining: Making glass Demonstrate the formation of glass by making sugar glass or rock candy. Plenary: Thinking about ceramics Plus, Minus, Interesting: All ceramics should melt at 90 °C. (Possible answers: Plus – it would be easy (and cheaper) to mould ceramics into complex shapes; Minus – glass cookware would melt before water boiled; Interesting – would glass be less likely to shatter and therefore safer? (Some glasses do melt at about 200 °C.) of measuring crystal size. salicylate) onto warmed and chilled microscope slides. When the salol has solidified, students examine the samples using a hand lens or microscope. Demonstrate the formation of glass by making sugar glass or rock candy. Lesson 9Eb: Polymers Learning objectives Exemplar teaching activities Differentiation Resources skills Practical skills Developing Starter: Polymer properties Students work in groups to describe the general properties of polymers. Exploring: Polymer slime Resources from 9Eb n/a Students use 4% PVA solution, 4%
Recall that crude oil is the primary source of raw materials for the plastics industry. Recall what happens when monomers polymerise. Recall the names of some common artificial and natural polymers. Link the properties of common plastics to their uses. Securing Classify changes as exothermic or endothermic from temperature changes. Explain how the properties of a substance depend on the bonding and arrangement of atoms. Exceeding Model the formation of poly(ethene) using equations, symbols and particle diagrams. Identify the monomer structures in a given polymer chain. Working Scientifically Recall some methods by scientists comment on one another’s work (e.g. scientific journals, conferences). Describe the process of peer review. Explain why peer review is used. Evaluate peer review. Ask each group to look at some samples of polymers and then list the properties they think they have in common. Exploring: Polymer Students use 4% PVA solution, 4% borax solution to make slime. Explaining: Polymer formation and energy Demonstrate how nylon can be made from the reaction between hexane-1,6-diamine in water and either decanedioyl dichloride or hexanedioyl (adipoyl) dichloride in cyclohexane. Plenary: Thinking about polymers Odd One Out: glass, poly(ethene), copper. (Possible answers: glass is the only brittle material; glass is the only material made from sand; poly(ethene) is the only material made from oil; poly(ethene) is the only one that is elastic; copper is the only metal; copper is the only conductor of electricity; poly(ethene) is the only polymer.) Students can go on to consider the properties of slime. Explaining: Polymer formation and energy Students consider the energy changes involved in the reaction. Exploring Science. solution to make slime. Demonstrate how nylon can be made from the reaction between in water and either dichloride or hexanedioyl (adipoyl) in cyclohexane. Lesson 9Ec: Composite materials Learning objectives Exemplar teaching activities Differentiation Resources Maths skills Practical skills Developing Starter: Pykrete Tell students about pykrete, the composite material made by freezing Explaining: Composites Resources from 9Ec n/a
Developing Recall how metals are extracted from ores from the Earth’s crust. Recall that the extraction of some metals is more difficult than others, depending on the metal’s reactivity. Explain why some elements have been isolated for much longer than others. Securing Explain what happens in oxidation and reduction. Describe how metals are extracted from ores by heating with carbon and electrolysis. Explain why the method used to extract a metal is related to its position in the reactivity series and cost of the extraction process. Exceeding Describe the movement of ions in electrolysis. Explain how oxidation and reduction happen during electrolysis. Starter: Extracting metals brainstorm Ask students to work in to list bullet points about how metals occur in the Earth’s crust and how to obtain pure metals. Form groups and ask for group list of bullet points. Exploring: Extracting metals from metal oxides Students out experiments to extract metals from four metal oxides, by heating with carbon (powdered charcoal). Explaining: Electrolysis of molten zinc chloride Demonstrate the decomposition of zinc chloride into zinc and chlorine using electrical energy. Plenary: Thinking about metals Plus, Minus, Interesting: Aluminium is extracted from aluminium oxide using electricity. (Possible answers: Plus – aluminium is available to make many objects, such as aircraft, foil, drinks cans; Minus – the extraction is expensive; Interesting – when aluminium was first extracted, it was more valuable than silver.) Exploring: Extracting metals from metal oxides Students can write balanced equations for the reactions taking place. Resources from 9Fe Exploring Science. n/a Students carry out experiments to extract metals from four metal oxides, by heating with carbon (powdered charcoal). Demonstrate the decomposition of zinc chloride into zinc and chlorine using electrical energy. Written by Mark Levesley, Iain Brand, Penny Johnson, Sue Kearsey and Sue Robilliard.