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Pearson Edexcel GCSE (9-1) Sciences Term 2 detailed summer planning document

Simple, inclusive, inspiring.

This planning document summarises the lesson ideas and digital resources contained in the second term of the Edexcel GCSE (9-1) Year 9 Free Teaching and Learning Support.

The document also details the practical activities in the free support and the equipment needed to run them. Core practicals are in italics.

Additional teacher guidance, student book pages, worksheets and answers will be available from December 2015.

To sign up for the free support materials please click here.

Please note: Resources and lesson ideas are awaiting endorsement by Edexcel. The specification is the draft specification published by Edexcel.

© Pearson Education Ltd 2015. Copying permitted for registered institution only. This material is not copyright free.

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Biology Spec points covered Starter Practical activity Teacher-led activity

CB2a Mitosis B2.1

B2.2

B2.3

B2.4

Describe mitosis as part of the cell cycle including the stages interphase, prophase, metaphase, anaphase and telophase and cytokinesis

Describe the importance of mitosis in growth, repair and asexual reproduction

Describe the division of a cell by mitosis as the production of two daughter cells, each with identical sets of chromosomes in the nucleus to the parent cell, and that this results in the formation of two genetically identical diploid body cells

Describe cancer as the result of changes in cells that lead to uncontrolled cell division

Ask students to identify what is needed for humans to grow, and establish the idea that new cells are important. Then ask students to identify the point where growth stops. Challenge them to say whether cell division to produce new cells therefore stops at this point as well. Elicit the idea that although adults do not grow in height, they still need to produce new cells. Tell students that new body cells are produced by a form of cell division, which we call mitosis.

Use a light microscope to look at mitosis in plant cells. Root tip squashes are prepared as part of the practical.

Students should be able to identify the different stages of the cell cycle from the prepared slides or the slides they have prepared themselves.

Equipment: If preparing own slides: garlic clove with roots, distilled water, paper towel, microscope slides and coverslips, watch glass or small dish, microscope with x 100 and x400 magnifications, fine forceps, pencil with rubber end, hollow glass block with few drops of hydrochloric acid, toluidine blue stain in dropping bottle, soft tissue, beaker of tap water, eye protectionIf using pre prepared slides: prepared and labelled slides of each phase of mitosis, microscopes with x100 and x400 magnificationsOptional: digital microscope

Model mitosis using clothes pegs with the spring removed from the middle. To help describe the duplication of chromosomes during cell division, show students the clothes peg. From one side it will look like a ‘one-chromatid chromosome’, but turned to the wider side it will look like two chromatids, which can then be divided up into two separate chromosomes.

Digital resource: Mitosis video


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CB2b Growth B2.5

B2.7

B2.6

Describe growth in organisms, including:(a) cell division and differentiation in animals …

Demonstrate an understanding of the use of percentiles charts to monitor growth

Explain the importance of cell differentiation in the development of specialised cells

Students should work in small groups to list as many examples as they can remember of different kinds of cell in the human body. They should then add any details they remember about the cells, such as where they are found, what they do, and what is special about them

Students use a microscope to look at prepared slides of specialised human cells. Display on the board a list of the specialised cells on the slides, but not in the order that the slides are labelled. You may need to indicate where to look for some of these in the tissues, for example ciliated and other epithelial cells line the edge of a tissue.

Adaptations of cells in slides suggested: red blood cells are red because they contain haemoglobin that combines with oxygen for transport around the body; muscle cells contain proteins in the cytoplasm that allow the cell to contract; neurones have a long fibre that carries electrical signals around the body; fat cells store large amounts of fat in droplets in the cytoplasm; a sperm cell has a tail that helps it move through the female reproductive system to reach the egg for fertilisation; an egg cell has a large amount of food in the cytoplasm to provide energy for cell division and growth after fertilisation; ciliated cells have cilia (fine

Show students a block of steel, or some steel car parts such as screws, and a car (or image if not available). Suggest that the objects could be used to model unspecialised and specialised cells, by using the steel to represent an unspecialised cell, while the steel car parts represent 'specialised' cells.

Digital resource: Specialised cells video

Discuss a percentile growth chart and how a data set is split into percentiles.

Digital resource: Interpreting growth curves presentation


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hairs) on their surface to move substances or objects (e.g. egg cell in oviduct) along the tube that the cells line; villi are covered in cells that have microvilli (brush border), which increases the surface area for absorption of digested food.

Equipment: prepared and labelled slides of human cells and tissues (see above for suitable examples), light microscope and light source

CB2c Growth in plants

B2.5

B2.6

Describe growth in organisms, including:...(b) cell division, elongation and differentiation in plants

Explain the importance of cell differentiation in the development of specialised cells

Ask students to work in pairs to jot down the names of at least five different plants. They should also note the ways in which their chosen plants look different. Take a few examples from around the class to get across the idea of variety of shape and form. Then ask what causes the plants to look different. Explain that the variation we see is due to different types and arrangements

Students work on measuring the increase in the mass of seedlings over four sessions within a two-week period. Trays of seedlings will need to be kept in a well-lit area between lessons. There should be an increase in percentage gain in mass over time. Ideally the graph of these values should show a smooth curve, but may vary depending on the constancy of conditions in which the seedlings are kept. If they vary, discuss with students possible reasons for this.

Either use a prepared slide of a longitudinal section of a root, or a photo of one from the internet. Make sure the section extends from the root tip as far back as the zone where the root hair cells are found. Display the image on the board and, starting at the root tip, point out the following features:● root cap● meristem● zone of elongation


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of cells in each type of plant. Equipment: Tray of at least

40 seedlings (fast growing, e.g. mustard, cress or fast-cycling brassica) grown on a damp absorbent surface such as paper towel or capillary matting, blunt forceps, balance accurate to 0.01 g, beaker of tap water for rinsing seedlings, sheet of paper towel, petri dish base or lid or other shallow container, water for watering seedlings.

● zone of differentiation:

Note that the cells begin to look different in terms of size across the root, as cells in some areas elongate faster than others. However, true differentiation occurs when cells develop special features that are related to particular functions. Ask the students questions as appropriate, such as:● what do the cells

look like in the meristem, and why are they like that?

● what causes the root to get longer?

● which kinds of specialised cells are obvious in the root and what do they do?

Digital resource: Specialised plant cells


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presentation

CB2d Stem Cells B2.8

B2.9

Describe the function of embryonic stem cells, stem cells in animals and meristems in plants

Discuss the potential benefits and risks associated with the use of stem cells in medicine

Give students a minute or two to jot down as many different kinds of cells in their body as they can think of. Take a selection from around the class and then ask where those cells came from. Try to elicit the idea that they all came originally from the division and subsequent differentiation of very similar cells in the embryo.

Student grow new plants from small pieces of cauliflower tissue. This shows students how stem cells in the meristem of the original plant tissue can divide and produce specialised cells in the shoots and stems of the new plants. The explants should show signs of greening and growth within about 10 days.

Equipment: Preparation before lesson: plant tissue culture medium containing 4.44 g Murashige and Skoog (M&S) medium, 20 g table sugar (sucrose), 7 g agar, kinetin stock solution (10 mg dissolved in 10 cm3 70% ethanol); SCIDN solution made up from one ‘Milton’ (800 mg SDICN) tablet in 100 cm3 distilled water. Sterile screw-topped bottles (e.g. Diluvials), microwave oven, heatproof glass jugs or 1 dm3 glass beakers, plastic film, stirrers, fume cupboard (if available), 0.1 M potassium hydroxide, pH meter, accurate balance,

Use a range of coloured beads or buttons, or coloured dots on a presentation, to help students visualise the gradual development of stem cells into specialised cells. Start with a single bead at the top. Identify that it represents a stem cell, like one in an early embryo that is able to produce any kind of specialised cell. Explain that, like all kinds of stem cell, when it divides it can produce identical stem cells or cells that develop into slightly specialised cells. Model the latter by adding two beads of different colours below the top bead.Explain that these new, slightly specialised cells are also stem cells because they are able to produce a range of specialised cells, but they are each only able


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pipettes, fridge for storing vials, cauliflower ‘head’ broken into floretsFor students: forceps in beaker of sterilising solution (SDICN), 70% ethanol, paper towel, small piece of cauliflower (‘floret’), scalpel, screw-lid jar of sterilising solution (SDICN), empty beaker (for collecting waste), tube with screw-topped lid (e.g. Diluvial) containing growth medium, clean tile, marker pen, access to light bank or well-lit window

to produce a particular range of types. These slightly specialised cells also divide to produce more identical cells, or cells that develop into even more specialised cells. Continue the diagram for another level or two. Ideally, use a graduation in tint for each ‘cell line’. Point out the beads in the bottom row and explain that these are fully specialised body cells, which are unable to produce any other type of cell.

Digital: Stem cells video

B2e The nervous system

B2.13 Explain the structure and function of sensory neurones, motor neurones and synapses in the transmission of electrical impulses including the axon, dendron, [myelin sheath and the role of neurotransmitters]

Ask students how many senses they think they have and their reasons for thinking this. Elicit the idea of what a sense is and hint at the fact that there are more than five. There is actually a long list of them, including touch, pressure, hearing, sight, taste, smell,

Students use a ‘touch tester’ with two points to find out which parts of the arms and hands are the most sensitive to touch. Students should discover that the tip of the middle finger is the most sensitive area and the outside upper arm the least.

Hold out an arm with your fingers straight and your thumb up. Tell students that this is a model of the neurone (dendrites – fingers, dendron – palm, cell body – thumb, arm – axon). Ask students which features of the cell are represented by


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balance, temperature, motion and tension in muscles, urine in the bladder, hunger and thirst. Point out that our bodies sense things both around us and inside us.

Equipment: blindfold, ruler, ‘touch tester’ made from a U-shaped piece of wire (e.g. unbent paper clip), a pair of compasses without the very sharp points, or two cocktail sticks pushed into sticky putty or cork (e.g. a wine cork) or taped to a vernier calliper or micrometer

the different parts of your arm and hand model.

Ask students to say how they would use this neurone model to model a nerve (take lots of arms in this position and wrap them together!).

Digital: Senses video

CB2f Neurotransmission speeds

B2.13

B2.14

Explain the structure and function of sensory neurones, motor neurones and synapses in the transmission of electrical impulses including the [axon, dendron,] myelin sheath and the role of neurotransmitters

Explain the structure and function of a reflex arc including sensory, relay and motor neurones

Show students a clip about a quadriplegic from a video storage site by using a search term such as ‘Christopher Reeve talks wheelchair’. Ask students why they think the person in the clip considered it important to appear on TV/in a video and what the nature of his/her accident was. Elicit the idea that the spinal cord has been damaged, preventing impulses from sense organs below the neck reaching the brain and also preventing impulses from the brain reaching

Investigate the speed of transmission of electrical impulses in the nervous system. Students work in groups to calculate the mean speed of an impulse.

Students are likely to calculate speeds of about 10 m/s. This is somewhat slower than the speed at which an impulse is actually transmitted along a neurone because the investigation involves many other factors (including synapses, brain processing and students’ reaction times), which slow the process down. In the body there are a range of different types of neurones,

Demonstrate some reflex actions:Dim the lights so that students observe each other’s pupils growing in diameter, and then shrinking again once the lights are turned back on. Ask a student to kneel on a chair, with his/her ankles hanging down loosely. Gently tap the Achilles tendon at the back of the ankle and the foot should swing outwards. Ask a student to sit with his/her legs crossed so that one leg hangs


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the parts of the body below the neck.

which will transmit impulses at different speeds, usually between 20–100 m/s.

Equipment: stopwatch, tape measure

freely. Gently tap under the knee cap with the side of your hand to see the knee jerk reflex action (or patellar reflex).

You can point out that the ankle and knee jerk reflexes are part of a system that detects slight variations in position and causes muscles to relax and contract accordingly, helping you to stand.

Digital: Reflex arc interactive

CB3a Meiosis B3.3

B3.5

Explain the role of meiotic cell division, including the production of four daughter cells, each with half the number of chromosomes, and that this results in the formation of genetically different haploid gametesThe stages of meiosis are not required

Describe the genome as the entire DNA of an

Write the following words on the board: cell, chromosome, DNA, gene, nucleus. Challenge students to work in groups to produce a labeled drawing to show the relative positions of these features. Ask students for ideas on what the term ‘genome’ means and establish that this describes all the DNA

Students should produce a poster showing the main events that take place during meiosis.

Use dark and pale socks to allow you to model the behaviour of ‘sets’ of chromosomes with dark colours being one set and pale colours being the other. String can be used to model the nuclear and cell surface membranes.

Digital: Meiosis animation


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organism and a gene as a section of a DNA molecule that codes for a specific protein

in an organism.

CB3b DNA B3.4

B3.6

Describe DNA as a polymer made up ofa two strands coiled to form a double helixb strands linked by a series of complementary base pairs joined together by weak hydrogen bonds

Investigate how to extract DNA from fruit

Show students a clip from the news or a detective/crime programme with Schene of Crime Officers at work. Ask students what is going on and what sort of evidence is being looked for. You should get the answer ‘DNA’ amongst others – if not, make the suggestion yourself. Write ‘DNA’ on the board and ask students where it is found in the body and why it can be used to convict criminals. Discuss their answers.

Student extract DNA from peas. Students should be able to obtain a white layer of DNA in their tubes.

Equipment: 100 cm3 measuring cylinder; two 250 cm3 beakers; 100 cm3 beaker; granular sodium chloride; frozen peas (thawed), or banana or other easily-mashed fruit; balance; washing-up liquid; pestle and mortar; water bath at 60°C; filter funnel; filter paper; clamp and stand; boiling tube and rack; pipette; protease solution (e.g. Novozymes® Neutrase®, powdered meat tenderiser (often found in Oriental/Asian food stores), fresh, unpasteurised papaya or pineapple juice, or contact lens cleaning solution); ice-cold ethanol; stirring rod.

Ensure that students understand that the term ‘complementary’ means ‘fitting together’ (rather than ‘matching’). Illustrate this by using jigsaw pieces, Lego® or pieces of quick-fit lab apparatus to show that parts fit together when one part is complementary with another. A useful model by which to demonstrate base pairing is to compare standard Lego® with Duplo® - two colours of Lego® (to represent A and T) and two colours of Dulpo® (to represent C and G). A and T are complementary with one another and although they have a similar shape to Duplo® (they are bases), they are not complementary


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with Duplo®.Point out that the sugar in DNA is called ‘deoxyribose’ and it’s why DNA’s full name is deoxyribonucleic acid.

Digital: DNA Structure presentation

CB3c Alleles B3.12

B3.13

B3.14

Explain why there are differences in the inherited characteristics as a result of alleles

Explain the terms: dominant, recessive, homozygous, heterozygous, genotype, phenotype and zygote

Explain monohybrid inheritance using genetic diagrams […] and family pedigrees

Tell students that you have a purple-flowered pea plant and a white-flowered pea plant. Ask students what colour they think the offspring pea plants will be if these two plants are crossed (bred). Record the class votes for purple flowers, white flowers and lilac flowers. Come back to this vote at the end of the lesson, and repeat the vote. Then ask students to write down or say if and why they have changed their minds.

Use dark beads to represent the eye colour alleles of the mother and pale beads representing the partner’s genotype. Students take beads from the cup without looking and draw bar charts to show the three numbers of the three possible genotypes and genetic cross diagrams.

Equipment: 10 pale beads/buttons, 30 dark beads/buttons, 4 plastic cups (or other suitable containers), marker pen, graph paper.

Tell students that since the PTC-tasting allele is dominant we would expect more students to be able to taste it than those who cannot. Choose students to taste either PTC strip or a control strip without telling students which is which. Ask each student to taste his/her strip in turn and say whether they can taste a bitter substance. Record the findings on the board and then reveal which were the control strips. The finding that most (or all) of the subjects can detect PTC supports the idea that this phenotype is caused by a dominant allele.


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Digital: PTC and genetics presentation

CB3d Inheritance B3.14

B3.15

B3.16

Explain monohybrid inheritance using […] Punnett squares

Describe how the sex of offspring is determined at fertilisation, using genetic diagrams

Calculate and analyse outcomes (using probabilities, ratios and percentages) from monohybrid crosses and pedigree analysis for dominant and recessive traits

Tell students that humans have 23 pairs of chromosomes and one of these pairs is a pair of sex chromosomes, of which there are two types; X and Y. These chromosomes are what controls whether we are male or female. Males have XY and females have XX. Ask students to draw a genetic diagram to explain why about 50% of the UK population is male and about 50% of the population is female. Go through the answer on the board.

Use models to investigate inheritance by constructing a family pedigree for a family in which cystic fibrosis occurs. Students work in groups and discuss the clues in order to construct the pedigree. They then shade in the symbols to match the key.

Invite someone who suffers from a genetic disorder, or a spokesperson from a charity that represents people with a certain genetic disorder, to come to give a talk to the class.

Can people be tested for the allele? Why would they want to be tested? What should they do/not do if they are carriers? What are the options for couples who are both carriers but wish to have children?Alternatively use video supplied.

Digital: Cystic fibrosis video

CB3e Gene mutations

B3.19 State that most phenotypic features are the result of

Give students a few minutes to design a cat

Students use a simple eye colour scale to collect data on

Discuss the Human Genome Project and


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B3.20

B3.21

B3.22

B3.23

multiple genes rather than single gene inheritance

Describe the causes of variation that influence phenotype, includinga genetic variation – different characteristics as a result of mutation and sexual reproduction

Discuss the outcomes of the Human Genome Project and its potential applications within medicine

State that there is usually extensive genetic variation within a population of a species and that these arise through mutations

State that most genetic mutations have no effect on the phenotype, some mutations have a small effect on the phenotype and, rarely, a single mutation will significantly affect the phenotype

that has a few obviously mutant features. Then challenge them to write down the story of how the cat got its mutant features. (e.g. ionising ray or mutating substance), encourage them to think about what effect this must have on the cat's body to result in the changed characteristic.

Explain how mutations are really caused by mistakes in DNA, and that this changes the allele of a gene, and so the form of the characteristic that the gene produces.

the variation in eye colour in the class or other groups (e.g. families).

Students will need to decide on a question to answer using the data they will collect, and then decide on who they need to collect data from to answer that question.

Students create a tally chart and draw a frequency diagram.

Eye colour is an inheritable feature (as a result of several genes), so there should be evidence of this in the results.

Equipment: Images from the internet to identify the following main iris colours: blue, grey, green, light brown/amber, brown. Label the images with their colours. Additional features in the iris may be seen in different colours, e.g. spots or rings of brown or yellow, and so may need additional images if these are being recorded.

how evidence from genomes is now used to predict the risk of developing diseases that are affected by different alleles and whether a person may respond poorly to certain drugs.

Digital Genetic variation in plants video


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CB3f Variation B3.20 Describe the causes of variation that influence phenotype, includinga genetic variation – different characteristics as a result of mutation and sexual reproductionb environmental variation – different characteristics caused by an organism’s environment (acquired characteristics)

Ask students to work in pairs and to note down six examples of variation in human characteristics. For each example, they should identify how they vary (can the variations be grouped, as in eye colour, or do they show a range between two extremes, as in height).

Then ask what causes other examples of variation. Introduce the effect of the environment. Complete the discussion by considering which characteristics may be affected by both environment and genes.

This practical provides an opportunity to consider genetic and environmental variation within one set of characteristics, the shape and form of leaves.

Although leaves on the same tree have the same alleles, environmental conditions such as amount of light and warmth may vary on even a small scale. For example, leaves that are shaded by others are more likely to be larger and may be a different shade of green.

Equipment ruler, calipers, green colour chart, sealable collecting bags for leaves, labels for bags, marker pen, computer/tablet with spreadsheet application

Write up a list of characteristics on the board, then draw a Venn diagram on the board of two intersecting circles. Add at least one characteristic to each section of the diagram, and ask students to spot what the labels should be for each of the circles and for the area of intersection. Once students have identified the labels, ask them to suggest where the remaining characteristics should be placed within the diagram.

Digital Continuous or discontinuous presentation


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Chemistry Spec points covered Starter Practical activity Teacher-led activity

CC4a Elements and the Periodic Table

C1.13

C1.14

C0.1

Describe how Mendeleev arranged the elements, known at that time, in a periodic table by using properties of these elements and their compounds

Describe how Mendeleev used his table to predict the existence and properties of some elements not then discovered

Recall the formulae of elements, simple compounds and ions

Draw nine shapes on the board, e.g. three squares, three circles and three triangles. For each shape, leave one unshaded, one half shaded, and one completely shaded. Ask the students to sort the shapes into groups. There are different ways in which these could be sorted including number of sides and amount of shading. The exercise is intended to encourage students to think about how similar items may be sorted according to different properties.

Give students have nine element cards to sort (Li, Na, K; Mg, Ca, Sr; F, Cl, Br).

Students should produce three columns or rows in the order Li, Na, K; Mg, Ca, Sr; F, Cl, Br (or Li, –, K; Mg, –, Sr; F, –, Br, I).

Show how properties of an element in groups 1 and 7 can be predicted using the properties of nearby elements in the same group.Cut a piece of lithium and then potassium on a tile, describing the ease of cutting as you do this. Ask the students to predict what will be observed when attempting to cut sodium, then cut a piece of sodium and describe the ease of cutting. Lithium is the hardest and potassium is the softest.Show sealed samples of chlorine and iodine. Emphasise how, at room temperature, chlorine is a gas and iodine is a solid. Ask the students to predict the state of bromine, then show a sealed sample of bromine. This is liquid at room temperature and vapour may also be


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present.

Equipment: Eye protection, chemical-resistant gloves. Lithium, sodium, potassium. In small sealed containers, samples of chlorine, bromine (a few drops) and iodine (a few crystals). Tile, forceps, scalpel or small knife.

Digital Mendeleev’s Periodic Table presentation

CC4b Atomic number and the Period Table

C1.15

C1.16

Explain that Mendeleev thought he had arranged elements in order of increasing relative atomic mass but this was not always true because of the relative abundance of isotopes of some pairs of elements in the periodic table

Explain the meaning of atomic number of an element in terms of position in the periodic table and number of protons in the nucleus

Write some key words to do with atomic structure on the board, e.g. atom, proton, neutron, electron, nucleus, shell. Students work individually or in pairs to write definitions for these words.

Students carry out a practical in which they investigate some physical properties of metals and non-metals. They test various solids (aluminium, copper, sulfur, carbon) for their electrical conductivity, malleability, appearance and density.

Equipment: eye protection; battery, bulb, wires with crocodile clips; small hammer; heat-resistant mat or wooden board; paper towels; 50 cm3

Work through with students: the recall of some chemical symbols for elements; how Mendeleev organised the elements into a table; Mendeleev’s use of his tables to make predictions about elements not yet discovered. The focus of the lesson may depend upon the prior knowledge and understanding


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C1.17

C1.18

Describe that in the periodic tablea elements are arranged in order of increasing atomic number, in rows called periodsb elements with similar properties are placed in the same vertical columns called groups

Identify elements as metals or non-metals according to their position in the periodic table

measuring cylinder; ±0.1 g balance; aluminium, copper, sulfur, carbon (graphite and charcoal) – sized to fit in the measuring cylinder.

demonstrated by the students in the Starter activity.

Digital Element discovery presentation

CC4c Electronic configurations and the Period Table

C1.19

C1.20

Predict the electronic configurations of the first 20 elements in the periodic table as diagrams and in the form, for example, 2.8.1

Explain how the electronic configuration of an element is related to its position in the periodic table

Draw diagrams to show the electronic configurations for sodium and oxygen, and write their configurations as 2.8.1 and 2.6. Challenge students to spot the links between these models: the number of numbers in a written configuration is equal to the number of circles drawn; each individual number represents the number of dots or crosses on a circle; the numbers are shown in order (from

Students produce their own element sheets by:● writing electronic

configuration, name and atomic number on one side

● drawing the electronic configuration diagram and atomic number on the other side.

Allocate each student one element from H to Ca (there may be duplicates). Students organise the sheets on the floor into atomic number order (as in the periodic table). When complete and checked,

Outside, chalk four circles on the ground to represent shells. Each student represents electrons (the teacher or a student could represent the nucleus). Starting with the inner circle, the students occupy each circle following rules for electronic configurations. Extra students in a large class may be used to call out or record the identities of the elements formed


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inner circle to outer circle).

discuss the links between position, atomic number and electronic configuration.

When the sheets are turned over it should reveal:● period number = number of

shells● group number = number of

electrons in outer shell (except for group 0, which is full)

● sum of numbers = atomic number.

Equipment: A4 or A3 (better) paper

and/or to capture the activity using smartphones/tablets/cameras.

Digital Electrons and groups presentation

CC5a Ionic bonds C1.21

C1.22

C1.23

C1.24

Explain how ionic bonds are formed by the transfer of electrons between atoms to produce cations and anions, including the use of dot and cross diagrams

Recall that an ion is an atom or group of atoms with a positive or negative charge

Calculate the numbers of

Teacher demonstrates that show energy is released when certain metal + non-metal compounds are formed. For example, magnesium + oxygen, iron wool + oxygen, sodium + chlorine and copper foil + chlorine. Class discusses how chemical reactions often involve a release of

Students complete target diagrams for different elements, state the number of electrons lost or gained to form an ion and add atom and ion symbols. They are then asked to organise the cards in the same way as the elements are arranged in the periodic table.

The arrangement of the information cards into a periodic table form should show

Start with the idea that atoms form bonds to become more stable, like the noble gases. Then explain the formation of ions and ionic bonds, linking the ion formed with the periodic table and using dot and cross diagrams to illustrate what happens when ions are formed. Stress that as


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C0.1

protons, neutrons and electrons in simple ions given the atomic number and mass number

Explain the formation of ions in ionic compounds from their atoms, limited to compounds of elements in groups 1, 2, 6 and 7

Recall the formulae of elements, simple compounds and ions

energy and that the products of these reactions are therefore more stable (less reactive) than the reactants. This should lead to the idea that energy is given out and atoms become more stable when they form bonds. Inform students that the all compounds produced in the demonstration contained the same kind of bonds called ionic bonds.

Equipment: 2 gas jars of oxygen; 2 gas jars of chlorine; cleaned piece of magnesium ribbon; small piece of sodium; iron wool (steel wool); copper foil (Dutch foil); tongs and deflagrating spoon.

there is a trend in ion formation across the main groups of the periodic table. (1+. 2+. 3+, 4+ or 4-, 3-, 2-, 1-.)

electrons are negative the loss of an electron forms a positive ion as students can find this confusing.

Digital Dot and cross diagrams presentation

C5b Ionic lattices C1.25 Explain the use of the endings –ide and –ate in the names of compounds

Recall the formulae of

Ask students to explain this (very) old chemistry joke:A sodium atom bumped into a chlorine atom in

Students use information about ionic bonds, ion size and electrostatic forces to make and evaluate a model of the ion structure in sodium chloride.

Explain ionic lattice structures; what they look like, how they are formed and how they influence the crystal


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C0.1

C1.26

C1.27

elements, simple compounds and ions

Deduce the formulae of ionic compounds (including oxides, hydroxides, halides, nitrates, carbonates and sulfates) given the formulae of the constituent ions

Explain the structure of an ionic compound as a lattice structurea consisting of a regular arrangement of ionsb held together by strong electrostatic forces (ionic bonds) between oppositely-charged ions

the street. When they picked themselves up the sodium atom looked distressed. The chlorine atom said, “what’s wrong?” “I’ve lost an electron,” said the sodium atom. The chlorine atom said “are you sure?” “Yes.” said the sodium atom, “I’m positive.”

Students use polystyrene balls (or similar) and cocktail sticks to make a model of the ionic lattice formed by sodium chloride. When evaluating their models, students should note good and bad points.

Students should form a 3 3 cubic lattice with alternate Na+ and Cl- ions.

Equipment: per group: 13 small polystyrene balls labelled (Na+ - sodium ions) 14 large polystyrene balls (Cl- - chloride ions) and 60 cocktail sticks. (The chloride ions should be roughly twice the size of the sodium ions)

structure of ionic solids.

Demonstrate how ionic formulae can be worked out using the cross-over method. Start with simple examples and move onto include those that involve polyatomic ions. Ensure students understand that the number ‘1’ is not written in formulae.

Digital Crossover method presentation

C5c Properties of ionic compounds

C1.32 Explain the properties of ionic compounds limited to:a high melting points and boiling points, in terms of forces between ionsb whether or not they conduct electricity as solids, when molten and in aqueous solution

Set up a circuit with a low voltage power supply, graphite electrodes and a lamp. Place the electrodes into a spatula of solid sodium chloride crystals in a small glass beaker and show that the lamp does not light up – so solid

Students test six substances and identify which of them are ionic compounds.

Students should find that copper sulfate, potassium iodide and sodium chloride are ionic compounds.Ethanol, sugar and water are

Explain what happens during electrolysis using a model or digital animation. If a magnetic model is available, the ions can be separated to represent melting and they can then move from one electrode to


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sodium chloride does not conduct electricity. Remove the electrodes, add about 40 cm3 distilled or de-ionised water to the beaker of sodium chloride and stir to dissolve as much as possible. Replace the electrodes and the lamp lights, showing that sodium chloride solution does conduct electricity.Ask the students to explain these observations

Equipment d.c. power supply, connecting leads and crocodile clips, two graphite electrodes, lamp in a holder, 100 cm3 glass beaker, glass rod, sodium chloride (salt) crystals, distilled or de-ionised water, optional: sticky notes or mini-whiteboards

not ionic compounds.

Equipment each group needs: boiling tube with bung to fit, 100 cm3 beaker, d.c. power supply, dropper pipette, eye protection, two graphite electrodes, lamp in a holder, leads and crocodile clips, spatula, substances to test – copper sulfate, ethanol, potassium iodide, sodium chloride, sugar and distilled or de-ionised water

another, so molten ionic compounds do conduct electricity. Emphasise that charged particles that can move are needed for a substance to conduct electricity. Ionic compounds always contain ions, which are charged particles. Show that the ions are held in fixed positions in the solid state so they cannot move from one electrode to the other, and so solid ionic compounds do not conduct electricity.

Equipment d.c. power supply, lamp in a holder, two graphite electrodes, connecting leads and crocodile clips, evaporating basin, spatula, Bunsen burner, tripod, gauze, heat-resistant mat, goggles or face shield, zinc chloride (few grams), model of an ionic compound, blue


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litmus paperAccess to a fume cupboardOptional: magnetic model of an ionic compound, webcam or video projector

Digital: TBC

C6a Covalent bonds

C1.28

C1.29

C1.30

Explain how a covalent bond is formed when a pair of electrons is shared between two atoms

Recall that covalent bonding results in the formation of molecules

Explain the formation of simple molecular, covalent substances, using dot and cross diagrams, includinga hydrogenb hydrogen chloridec waterd methanee oxygenf carbon dioxide

TBC TBC TBC


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CC7a Molecular compounds

C1.33

C1.38

Explain the properties of typical covalent, simple molecular compounds limited toa low melting points and boiling points, in terms of forces between molecules (intermolecular forces)b poor conduction of electricity

Describe, using poly(ethene) as the example, that simple polymers consist of large molecules containing chains of carbon atoms.

TBC TBC TBC

CC7b Allotropes of carbon

C1.34

C1.35

C1.36

Recall that graphite and diamond are different forms of carbon and that they are examples of covalent giant molecular substances

Describe the structures of graphite and diamond

Explain, in terms of structure and bonding, why graphite is used to make electrodes and as a lubricant, whereas

TBC TBC TBC


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C1.37

diamond is used in cutting tools

Explain the properties of fullerenes including C60 and graphene in terms of their structures and bonding

CC7c Properties of Metals

C1.39

C1.41

Explain the properties of metals, including malleability and the ability to conduct electricity.

Describe most metals as shiny solids which have high melting points, high density and are good conductors of electricity whereas most non-metals have low boiling points and are poor conductors

TBC TBC TBC

CC7d Models C1.40

C1.31

Describe the limitations of particular representations and models to include dot and cross, ball and stick models and two- and three-dimensional representations

Explain why elements and compounds can be classified

TBC TBC TBC


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asa ionicb covalent, simple molecularc covalent, giant moleculard metallicand how the structure and bonding of these types of substances results in different physical properties, including relative melting point and boiling point, relative solubility in water and ability to conduct electricity (as solids and in solution)


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CP3a Energy stores and transfers

P1.29

P1.30

P1.31

P1.32

Explain, with examples, that, where there are energy transfers in a system, there is no net change to the total energy of a closed system

Analyse the changes involved in the way energy is stored when a system changes, including:a an object projected upwards or up a slopeb a moving object hitting an obstaclec an object being accelerated by a constant forced a vehicle slowing downe bringing water to a boil in an electric kettle

Use diagrams to represent energy transfers and calculate the before and after energy values

Explain that, in all system changes, energy is dissipated so that it is stored in less useful ways

Ask students to write a short story to illustrate different energy stores and transfers. Students can either highlight or label the different energy stores/transfers in their stories, or volunteers could be asked to read out their stories and the class identify the stores and transfers as the story is read. They could also be asked to suggest any transfers or stores not mentioned in the story.

Students work in pairs or small groups, depending on the availability of equipment, to undertake a series of brief practical investigations to observe a series of energy transfers from one store to anotherStudents identify the energy stores and transfers involved in each demonstration they look at.Equipment battery-powered torch (could be a circuit with cell and lamp); electric motor (could be set up to lift something); baby’s rattle; microwave oven; a solar cell (could connect to output device like a fan, or just to a voltmeter); a weight going over a pulley to drag a wooden block along the desk (this could be a dynamics trolley); radio; wind-up torch; toy on a spring that bounces up and down; computer animation of a nuclear reactor in operation (the computer’s energy transfers could be an additional discussion question); a Bunsen burner heating water (include a thermometer clamped to show

Set up a simple pendulum and start it swinging. Elicit the idea that the initial store of gravitational potential energy from lifting the bob is transferred to kinetic energy and back to potential energy, and that air resistance (and friction in the pivot) will eventually slow it to a stop. This happens as the moving pendulum transfers some of its kinetic energy to kinetic energy of the surrounding air particles. Eventually all the energy initially given to the pendulum will be transferred by heating to the surroundings. Then drop a ball onto the bench, and let it bounce until it stops. The energy changes here are between gravitational potential energy, kinetic energy and elastic potential energy when the ball


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the temperature - heated water will need to be replaced by cold water regularly); sonometer or stringed instrument (the instructions should include pausing when the string is stretched so that elastic potential energy is included.)

deforms on hitting the bench. As before, all the gravitational potential energy originally stored in the ball is eventually dissipated to the surroundings by heating. Equipment: Pendulum: clamp and stand; weight; string or threadBouncing ball: ball that bounces several times before stoppingDigital Explaining properties animation

CP3b energy efficiency

P1.38

P1.39

P1.33

Calculate efficiency in energy transfers, and explain how efficiency can be increased

Recall and use the equation:

efficiency = (useful energy transferred by the device) (total energy supplied to the device)

Explain that mechanical processes become wasteful

Draw two Sankey diagrams on the board for similar appliances with the same energy inputs but different proportions of useful and wasted energies output.

Ask students to describe what the two diagrams show, elicit ideas about the differences between the energies transferred by the two objects, and

Students work out the efficiency of an electric kettle by measuring the time taken to boil water. Students then calculate the efficiency of the kettle in boiling the water.

Kettle efficiencies should generally be quite high (of the order of 0.8 or above).

Equipment: electric kettle(s) with auto-shut-off (If various kettles with different power

Find one or more news reports on the internet from 2014 when an upper limit on the power of new vacuum cleaners was imposed and resulted in panic buying before the deadline. Explain that power is a measure of energy transferred each second, and ask for suggestions why this was done. Question


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P1.36

when they cause a rise in temperature so dissipating energy in heating the surroundings …

Explain ways of reducing unwanted energy transfer including through lubrication ...

discuss what could be used as the measure of energy wasted – elicit the idea that comparing the amount of useful (or wasted energy, at this point in the lesson) to the total energy transferred to the appliance is a more useful measure than just looking at the amount of wasted energy.

ratings can be provided, then this experiment can be repeated to find out, for example, if higher power kettles are more or less efficient.); measuring cylinder/beaker (500/1000 ml); stopclockOptional: temperature sensing datalogger.

students to elicit the idea that the limit on power will encourage manufacturers to develop more efficient machines, so that they end up with a vacuum cleaner that uses less energy for the same performance.

Digital Efficiency calculations presentation

CP3c Supplying electricity

P1.33

P1.34

P1.35

Explain that mechanical processes become wasteful when they cause a rise in temperature so dissipating energy in heating the surroundings or when they do electrical work against resistance of connecting wires.

Explain why electrical energy is transmitted at high voltages, as it improves the efficiency by reducing heat loss in transmission lines

Explain where and why step-

Hold a short brainstorming session to elicit words connected with the transmission of electricity around the country (e.g. power station, pylon, cables, substation). Ask students to suggest what these things are for, and then to work in pairs or small groups to write a short paragraph to explain their ideas.

Students to compare the energy transferred by a bulb close to a power pack and connected to the power pack by lengths of resistance wire.

Students should find that the energy transferred to the distant bulb is significantly less than to the bulb close to the power pack.

Equipment: power pack; 2 x 1 metre lengths of 24 SWG nichrome wire; connecting wires, crocodile clips; 2 12 V bulbs, 2 voltmeters, ammeter

Demonstrate the effect on transmission losses of increasing the voltage of a supply by using a 12 V a.c. supply connected to two metre-long lengths of resistance wire. Connect a bulb across the supply and another across the ends of the resistance wires. Switch on and ask students to compare the brightness of the two bulbs.Then connect a transformer to the output of the


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P1.36

up and step-down transformers are used in the transmission of electricity in the National Grid

Explain ways of reducing unwanted energy transfer including through … lubrication, thermal insulation and low-resistance wires

powerpack, set up to increase the voltage to 240 V, and another at the other end to step it down to 12 V again. For this part of the demonstration the lengths of resistance wires should be insulated inside a plastic sleeve. Ask students to compare the brightness of the bulbs.

Equipment:12 V a.c power supply; connecting leads and crocodile clips; 2 x 1 metre lengths of resistance wire; 2 transformers, set up with a turns ratio of 20; 2 x 12 V bulbs.Optional: 2 mulitmeters

Digital National grid interactive


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CP3d Keeping warm

P1.36

P1.37

Explain ways of reducing unwanted energy transfer including through … thermal insulation

Describe the effects of the thickness and thermal conductivity of the walls of a building on its rate of cooling qualitatively

Show students some images of energy-efficient houses, and ask them to explain what it means to refer to a house as 'energy-efficient'. Ask for suggestions as to what features of the house help with this and why, eliciting ideas about various insulation methods (e.g. double glazing, loft insulation, cavity walls, etc).

Students test the effectiveness of different types of insulation.

Water in beakers with insulation will cool down more slowly than in the control beaker. The rate of cooling will depend on the type and thickness of insulation used.

Equipment: kettle, 3 250 cm3 beakers, lids for beakers (discs of card with a hole for the thermometer), 3 thermometers, stopclock, selection of insulating materials (e.g. bubble wrap, fleece, various types of cloth, paper towels), sticky tape. Optional: temperature sensors and data logging equipment.

Wrap a piece of paper around the junction between the wood and metal in a wood and metal bar. Gently play a Bunsen burner flame on the paper. Students should be able to see that the paper that is over the wood begins to scorch; the paper over the metal does not. Elicit reasons for this (the metal bar conducts the energy throughout the bar, so does not get as hot where the Bunsen flame is heating it). Ask them to describe the wood and the metal in terms of their thermal conductivities.

Equipment: metal and wood bar; paper; Bunsen burner; smoke box; paper towel.

Digital Insulating houses video

CP3e P1.40 Describe the main energy Tell students that a new Students build a model steam- Use a model steam © Pearson Education Ltd 2015. Copying permitted for registered institution only. This material is not copyright free.

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Renewables

P1.41

sources available for use on Earth (including fossil fuels, nuclear fuel, bio-fuel, wind, hydro-electricity, the tides and the Sun), and compare the ways in which both renewable and non-renewable sources are used

Explain patterns and trends in the use of energy resources

power station is needed to make sure there is enough electricity for everyone in the country. Ask them which kind of fuel they would choose for their power station and why – elicit ideas about the availability of the fuel, and the environmental consequences of burning it.

driven turbine, to illustrate part of the process that happens in a fossil-fuelled or nuclear power station.

Equipment: two aluminium pie dishes, wooden dowel, Bunsen burner, tripod and gauze, scissors, drawing pin, stand and two clamps, 250 cm3 beaker of water, funnel (plastic if it can withstand steam, otherwise glass), eye protection.

engine to demonstrate one way in which the energy stored in a fuel is transferred to motion. If this can be connected up to a dynamo and light bulb, it can also be used as a model for a power station.

Equipment Model steam engine; fuel (depends on the type of engine, but often solid hexamine blocks/solid fuel tablets); dynamo; connecting wires; light bulb.

Digital Non-renewable energy video

CP3f Non-renewables

P1.40 Describe the main energy sources available for use on Earth (including fossil fuels, nuclear fuel, bio-fuel, wind, hydro-electricity, the tides and the Sun), and compare the ways in which both renewable and non-renewable sources are used

Write the phrase ‘NIMBY’ on the board and ask students if anyone knows what it means. If necessary, tell them that it stands for ‘not in my back yard’, and ask them to suggest why this phrase is often used when talking about

Students investigate the factors that affect the output of a solar cell, starting with the link between output current and the distance from the light source, then planning how to investigate a different factor.

The voltage will reduce as the lamp is moved further away.

Discuss what happens to the demand for electricity when a very popular TV programme finishes or when there is an advert break (e.g. during a live cup final or a popular soap). Elicit the idea that lots of people all getting up


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P1.41 Explain patterns and trends in the use of energy resources

people who are protesting against a new wind farm or other renewable ways of generating electricity.

Equipment solar cell, voltmeter (or multimeter), connecting wires, lamp, ruler, Optional: cardboard, protractor, coloured filters

to put the kettle on at once will cause a sudden demand. Ask students to suggest whether using fossil-fuelled power stations or hydroelectric power stations to meet a sudden demand would be best (hydroelectric, as there is very little time delay, whereas it takes some time to make steam). You could discuss that, for this reason, power stations are kept running even if they are producing more electricity than is needed. This is necessary because the relatively low amount of hydroelectricity generated in the UK.

Digital Renewable energy video

Written by Mark Levesley, Penny Johnson, Sue Kearsey, Iain Brand, Nigel Saunders, John Ling and Sue Robilliard.


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Some content is adapted from existing material originally authored by Ann Fullick, James de Winter, Mary Jones, Jim Newall, and Miles Hudson. Used with permission.


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