UNIT A + B

Food + Digestion

1F 1. Name the seven food groups which are essential for healthy living. 2. Which of the following groups is the best source of protein? a) bread / potatoes / cereals b) meat / eggs / fish c) butter / cooking oil / cream 3. Why are carbohydrates important for the body? 1H 1. Name the seven food groups which are essential for healthy living. 2. Which of the following groups is the best source of protein? a) bread / potatoes / cereals b) meat / eggs / fish c) butter / cooking oil / cream 3. Blood, teeth, nerves and the thyroid gland are kept healthy by taking the right amount of which food group? 4. Why are carbohydrates important for the body? 5. Why is it important to drink lots of water? 2F 1. What is meant by the word ‘digestion’? 2. What are the two main steps in the process of digestion? 3. In the diagram below, label the parts of the digestive system.

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2H 1. Copy and complete the following sentences about absorption by circling the correct word: Enzymes are used to break up / combine big molecules so that small ones can be made. These smaller molecules cannot / can pass through the gut wall into the blood. They then pass into / out of the cells and are used by the body. 2. Name the three different types of enzymes that bring about the changes below: starch glucose and other simple sugars protein amino acids fats glycerol + fatty acids 3. In which part of the digestive system is food absorbed? 4. In which part of the digestive system is water absorbed? 5. The small intestine is covered with millions of villi. What are villi and what is their job? 3F 1. How is food carried around the body? 2. Why do children need to eat more protein than adults? 3. Sailors in the past used to suffer from scurvy. Find out: a) What is scurvy? b) How does it affect the body? c) How did the Captains of ships try to prevent their sailors from getting scurvy? 3H H/W 3F then 4. Find out about one of the following diseases and what causes it. Beri-Beri Rickets Kwashiorkor 4F 1. a) What are enzymes used for in our bodies? b) Where would you find enzymes? 2. a) Name three foods high in fibre. b) How does eating these help your body? 3. a) Describe how food gets into your blood. b) What is this process called?

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4H 1. What are enzymes, what do they do and where are they found? 2. The graph shows the effect of temperature on the activity of the enzyme.

Rate of reaction

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20 30 40 Temperature oC

a) At what temperature is enzyme most active? b) Explain what is happening to the activity of the enzyme i) between X + Y ii) between Y + Z 3. What is absorption and where does it take place in your digestive system? 4. How is this part of the digestive system adapted to improve absorption, include a diagram of the adaptation. 5F 1. Copy and complete the word equation for respiration. The first letter of each word has already been put in. G………… + O………… = C…………d…………+ W……………+ E………….…. 2. The energy created from respiration is used by the body in many ways. List at least 6 ways you can think of. 5H Do H/W 5F then 3. A girl blows into a tube. The tube goes through a trough of iced water and then into a beaker containing limewater. After breathing into the tube, water residue was found in the U-tube and the limewater had gone cloudy. Explain why: a) there was water residue in the U-tube. b) the limewater was cloudy.

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6F The diagram below shows part of the respiratory system.

1. From the diagram, give letter which label: a) the trachea b) alveoli 2. a) Which gas passes into the blood from the alveoli? b) Which gas passes out of the blood into the alveoli? 6H H/W 6F then 3. The walls of the capillaries and the alveoli are very thin. Why do they need to be thin? 4. There are millions of alveoli in the lungs. They provide a very large surface area. Why is a large surface area necessary? 7F – Review/Revision Read through your notes then; 1. Answer the following questions: a) Use the words in the box to name the parts of the chest. lung rib windpipe air sac diaphragm

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bronchus

b) Use the words in the box to answer questions (i) to (iv) capillaries

heart

air sacs

oxygen

i) ………………………………. and carbon dioxide are exchanges in the lungs. ii) The lungs feel spongy because they contain tiny ………………….. iii) These are surrounded by small blood vessels called ……………………… iv) Blood from the lungs returns to the ………………. to be pumped around the body. 2. List the 7 main food groups with examples. 3. Write out the word equation for respiration and learn it. 7H Read through your notes then: 1. Write out a flow diagram to show the journey of an oxygen molecule from the nose to a leg muscle. Name each structure it passes through in the breathing and circulatory system. 2. Say where the reactants in respiration come from. 3. Write out and learn the word equation for respiration. 4. Why is it wrong to say respiration is breathing? 5. List the 7 main food groups and their functions.

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8C + D

Microbes + Disease, Ecological Relationships

1F Find as many examples of foods that contain fungus or bacteria, including yeast. Make a colourful poster showing these foods. Or Look in your kitchen for as many ways to keep food from spoiling as possible. Put these methods of saving food into a colourful poster. 1H Do 1F then: 1. What kinds of factors must you consider when you are designing packaging to preserve food. Think about the types of conditions bacteria and fungus need to survive – you want to prevent or slow down the growth of those micro organisms. 2. You are a health inspector in a school cafeteria where there has been an outbreak of food poisoning. List the ways that such an outbreak could be prevented in the future. Write about the way food should be prepared and stored and how clean the cafeteria should be. 2F Copy the sentences and fill in the gaps using the words in the box. immune natural

medicines white blood immunisation antibodies

cells defences

The body has its own _______________ _______________ against disease but it can be helped by _______________ and _________________. The main armies of defence of the body are ______________ and _______________ ______________ _____________________ which are part of the body’s defence system. 2H 1. How do each of these barriers protect your body against infection? a) skin b) lysozyme in tears and sweat c) mucous d) scabs e) cilia in lungs 2. Name three ways white blood cells defend the body against disease. 3. What good habits can protect us from getting the flu (think about what you eat and hygiene). 3F + H Spots may be caused by bacteria in the skin. A researcher investigated the effect of spot-lotion on bacteria. a) He grew bacteria on the surface of jelly in a Petri dish. At what temperature out of the four below would the bacteria reproduce quickly? 100oC 4oC 37oC -15oC

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b) The researcher places two small paper discs onto the surface of the jelly. One disc had been soaked in spot-lotion. The other disc had been soaked in water. The diagrams below show jelly at the beginning of the experiment and two days later.

at the beginning of the experiment

two days later

Suggest what had happened to the bacteria in the clear area around the paper disc soaked in spot-lotion. c) What was the control on this experiment? d) Give two safety precautions the researcher should take to avoid contact with the bacteria. 4F 1. What is a microbe? 2. When would you take an antibiotic? 3. Name three drugs that are legal in Britain? 4. Name three illegal drugs and the dangers of using them? 4H 1. Name three microbes which can cause disease. 2. Whar are antibiotics? 3. a) Name three drugs which are legal in Britain and what you might find in them. b) Name three illegal drugs and in what way are they harmful. 4. Describe in detail how to make an agar plate. 5. List four possible health risks in a kitchen. 6. Why do some people go to the doctors and have a ‘flu jab’?

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5F The drawing shows some of the animals which live at the bottom of the North Sea.

5H Buttercup plants grow mainly in open fields. Dog’s Mercury is a plant which grows mainly in woodland. The graph shows how the rate of photosynthesis in these two plants changes as the light intensity changes.

Why do Dog’s Mercury plants grow better than buttercups in woodland? Use the graph to help you. 6F + H 1. The drawing shows greenflies and ladybirds on a sunflower stalk.

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Look at the food chain sunflower

greenfly

ladybird

bird

a) What is the producer in this food chain? b) Which two living things in the food chain are predators? c) Why do sunflowers grow better if there are lots of ladybirds in the garden? 6H Do 6F then 2. Draw a pyramid of numbers for the food chain. 7F At Boffin Bay you can catch six kinds of fish. Boffin Bay Council has made this flow chart. It helps anglers who want to know what kind of fish they have caught. The shaded boxes tell them the name of the fish. START

Is the fish striped

Is the tail forked

Does the fish have 3 fins

Is the tail forked

Does the fish have 3 fins

Sea Flyer

Bracketeer

Snatcher

Addend

Thwait What kind of fish are these? (tails do not count as fins)

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Kiro

7H Do 7F and: Draw a table with the following headings: algae, conifer, flowering plant,

moss,

Put the following plants under the correct headings:rose, red sea weed, common fern, christmas tree, bracken strawberry, pine. 8F+H

fern.

daffodil, for tree,

Revision

1. Read and learn your notes thoroughly. 2. Write the meaning for 10 of the following words: food chain herbivore habitat virus antigen

producer omnivore population fungus immunity

consumer top predator camouflage pathogen

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carnivore prey bacteria antibody

grass, moss,

UNIT E+F

Atoms, Elements, Compounds and Mixtures

1F Copy the diagrams and write the sentences that apply to them underneath.

The particles are very close together. The particles are far apart. The particles move around very fast. The particles are quite close together. The particles can’t move around each other but they vibrate. The particles move about slowly. 2. Draw a table in your books with column headings solids, liquids and gases. Then sort the substances listed below into the correct columns. wax iron milk cheese oxygen lemonade nitrogen water ice steam air wood paper hydrogen mercury paraffin carbon dioxide 1H.

Julie holds a large plastic bag with a few polystyrene balls in it. She shakes it up and says: “I’ve made a model of a gas”. How could she use the same polystyrene balls: a) to make a model of a liquid? b) to make a model of a solid? 3. A teacher says to the class: ‘When you are sat down here in the classroom, you are like the particles in a solid in two different ways. When you leave the classroom and walk along the corridors, you are like the particles in a liquid in two different ways. But when you run around on the football pitch, you are like the particles of a gas in two different ways’.

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Explain what the teacher meant by each statement. 2F 1. Circles A, B, C, D and E show atoms of different elements. They are all mixed up.

Copy and complete the table. The first row has been done for you. Element Number of atoms in mixture A 4 B C D E

Percentage of atoms in mixture × 100 = 20%

2. For the following questions you must draw the correct diagram and give full answers to get an A or B. a) Which one of the following drawings A, B or C shows an element? Explain your answer.

b) Which of the following drawings D, E, F or G is; i) a solid element? ii) an element that is a gas? iii) an element that is a liquid?

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2H 1. Three of these sentences about compounds are true. Copy the true sentences down in your book. Every compound has a formula Compounds are simpler substances than elements Compounds are made from their elements by chemical changes Compounds contain elements chemically joined together Compounds are always solids 2. a) Write down the elements that make up each of the following compounds. Key : H = hydrogen,

O = oxygen,

N = nitrogen

b) i) What is the same about each of these? ii) What is different about each of these compounds? 3. Write down the elements in each of the two element compounds: magnesium oxide, hydrogen chloride, aluminium chloride, hydrogen sulphide

sodium chloride, copper oxide, calcium oxide,

iron sulphide, carbon dioxide, copper sulphide,

3F 1. The table gives the formulas of the substances in a lemonade drink: Substance Water Carbon dioxide Sugar Citric acid

Formula H2O CO2 C12H22O11 C6H8O7

Copy down the two sentences that best describe a lemonade drink: The drink is a mixture of solid, liquid and gas. The drink is a mixture of elements. The drink is a mixture of compounds. The drink is a compound. The drink is a mixture of un-combined elements.

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2. Two pictures show the molecules in different mixtures of hydrogen and chlorine and one picture shows the molecules in the compound hydrogen chloride.

a) Which two of A, B and C are the mixtures and which one is the compound? b) Copy out the five sentences below that are true. The compound contains only one kind of molecule. The mixtures contain only one kind of molecule. The compound contains only one kind of atom. The compound has a formula but mixtures do not. The formula of a compound cannot be changed. Both of these mixtures and the compound contain the same elements. The composition of the mixtures can be changed but the composition of the compound cannot be changed. In the mixtures, the elements hydrogen and chlorine are joined together chemically. Compounds and mixtures are always gases. 3H 1. a) Copy the following table. Then complete it by writing down the name of each element in the compound and how many atoms of the element are present in the formula. The first one is done for you. Key: Al = aluminium Cl = chlorine Cu = copper Fe = iron Na = sodium O = oxygen S = sulphur Formula NaCl MgO CuS MgCl2 Fe2O3 Al2O3

Elements and the number of atoms 1 atom of sodium, 1 atom of chlorine

b) Add a third column to your table and write down the name of each compound. Again the first one is done for you. Formula NaCl

Elements and the number of atoms 1 atom of sodium, 1 atom of chlorine

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Compound name Sodium chloride

2. a) Look at this drawing of a molecule.

i) Copy down the chemical formula below and complete it by writing one number only after each of the chemical symbols H and Cl. C3H Cl ii) Now write down in words and numbers which atoms are present in this compound, e.g. three carbon atoms. b) Copy the table below and complete it by writing in the name of the compound and the number of atoms of each element in the compound. The first one is done for you. Formula CuSO4 NaNO3 MgCO3 Na2SO4 CU(NO3)2 Al2(SO4)3

Name Copper sulphate

Composition 1 atom, 1 atom sulphur, 4 atoms oxygen

Key : Al = aluminium, C = carbon, Cl = chlorine, Cu = copper, Fe = iron, h = hydrogen, Na = sodium, N = nitrogen, O = oxygen, S = sulphur. 3. A chef mixes together the cake ingredients in the table. Ingredient Water Flour Fat Sugar Dried fruit

Mass in grams 300 400 200 100 200

a) What is the total mass of the ingredients before mixing? b) What will the total mass be after mixing? c) When the ingredients for the cake are mixed together nothing new is made. What kind of a change is this? d) The chef forgets to put the cake in the oven. A few hours later the chef weighs the mixture again and finds it now weighs slightly less than before. Write down a reason why this might have happened. e) Suppose the cake mix had been left in a sealed container. What would have happened to the mass if it had been left for a few hours? f) What needs to be done to the cake mixture to get a chemical change?

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4F For the following questions either copy the questions or give full sentences for your answers to get an A or B. 1. The following diagrams show two methods of separation.

a) What is the name of each method? b) Here are four mixtures. You can separate one mixture by method X and one mixture by method Y. Write down the mixture that can be separated by each with X or Y beside it. sand and iron filings ethanol and water

colours in an ink salt solution and sand

The diagram below shows the stages in getting pure copper (II) sulphate from copper ore.

c) Copy the diagram and complete the two labels on it. d) How would you get copper (II) sulphate crystals from the solution? 2. Here is a list of common gases. (The formula of each gas is also given to help you). chlorine (Cl2) methane (CH4) oxygen (O2)

hydrogen chloride (HCl) helium (He) sulphur dioxide (SO2)

a) Copy the table then put each gas from the list into the correct column of the table. You may write the names or the formula. element compound

b) When carbon is burnt in air it reacts with oxygen to form carbon dioxide gas. Write a word equation to show this reaction. 16

c) The boxes show some diagrams of particles. Draw lines to link oxygen and carbon dioxide molecules to their correct diagrams. Helium has already been done for you.

d) Air contains several gases including nitrogen, oxygen and carbon dioxide. Explain why it is a mixture and not a compound. e) When air is cooled it becomes a liquid. The gases in air have different boiling points. Name a process which could be used to separate the gases in the liquid. 4H Write full sentences for the answers so that they are useful as notes without this homework book. 1. An unknown pupil has used marker pens to write on the classroom wall. Mr Ward has discovered two pupils with sets of marker pens. He is going to use chromatography to investigate whose pens were used. He obtained samples of 3 different colour inks by wiping the writing on the classroom wall with cotton wool dipped in different solvents. The table shows his observations. Solvent Water Ethanol Hexane

Red ink No effect Some traces left Removed the ink

Green ink No effect Removed the ink Removed the ink

Blue ink No effect Some traces left Removed the ink

a) Explain which solvent would be most suitable to use for investigating the inks. b) Mr Ward used this apparatus to separate the dyes in the inks. Why was the base line drawn in pencil and not ink?

c) Here are the results of Mr Ward’s investigation. i) Which colour ink contained only one dye? ii) Explain how Mr Ward was able to decide which boy’s pen had been used for drawing on the classroom wall. c) Here are the results of Mr. Ward’s investigation. i) Which colour ink contained only one dye? ii) 17

2. a) Natural gas consists of a mixture of mainly methane (CH4) together with small amounts of other gases. Why is natural gas described as a mixture and not a compound? b) When methane burns it reacts with oxygen (O2) in air to form carbon dioxide and water. Copy and complete the following table by ticking one box and stating the number of atoms in one molecule of the substance. The first row has been done for you. Substance

It is an element

It is a compound √

carbon dioxide methane oxygen water

Number of atoms in one molecule 3

c) The diagram represents a mixture of methane and oxygen. In your books draw a similar diagram to represent a mixture of carbon dioxide and water.

d) Describe a chemical test you could do to show that a mixture of carbon dioxide and water has different properties from those of a mixture of methane and oxygen. 5F 1. a) Copy the diagram into your book and label it.

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c) List the physical processes involved in distillation. 5H 1. A rotovapour is a device used in laboratories to speed up distillation. The round bottom flask is tilted and rotated mechanically. The flask is also connected to a vacuum. Use you knowledge of partical theory to explain how these adaptations speed separation. 2. Separating sugar from a solution causes problems if the solution is heated in an evaporating basin with a bunsen flame. The sugar caramelises. a) Write a word equation to show caramelisation. b) Explain how you might be able to extract sugar without caramelising it. Imagine you are starting with some sugar cane. 6F+H Make posters to show the formation of compounds and mixtures and explain the differences between compounds and mixtures. 7F+H Revision 1. Read and learn all your notes. 2. Be able to describe a separation technique to a friend or member of your family in 60 seconds.

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Unit G+H

Rocks and Weathering

1F+H 1. A lump of sandstone and a lump of granite of the same size are put in water. Sandstone absorbs 10g of water. Granite absorbs 1g of water. a) Which one absorbs the most water? b) Do a drawing of the sandstone to show where the water has been taken in and hidden in the rock. 2. Copy and fill in the gaps from the words in the box. conglomerate

space

mineral

Rocks are made from grains of hard solid, sometimes called m………… Some grains interlock so there are no s………… between the grains: some are loosely packed and these are called ………………………… or sedimentary rocks. 3. Write half a side about a museum you have visited and say what the most interesting exhibit was. Go to the Natural History Museum on the internet. This is its address: http://www.nhm.ac.uk/ Make a simple word document about one of the galleries. 2F 1. Look at this picture of a famous statue. Water could wear it away.

Where is it and say how long it has been there. 2. Copy and fill in the gaps (some letters in the words are filled in for you): “Rocks of every sort and sh……..e are w…..n away over time. Weathering is the process which breaks rocks down into sm…….r bits. Water or r….n can cause rocks to weather. Water in small cracks fr……s and gets b…………r. The force caused by the ice forming makes the cracks l….r….r and in the end the rocks sp……t. This is called freeze-thaw weathering.

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2H Do 2F then: 3. Rock climbing. When a climber first climbs a rock face by a new route she is entitled to give a name to that route. The two in the picture of the 300m high rock face are called golden slipper and arcturus. Write two names of your own that you might give to a route that you first climbed. How will the climber change the rock as she climbs it?

She wrote “ The rough, pocketed rock is absolutely superb. This is the best of Pavey Ark’s rough ryhyolite crystals above the fault line of Jack’s Rake. Just the right side of vertical with little to nothing in the way of protection, this is an immaculate piece of climbing; always in balance, always interesting, delicate and exposed with the hardest boldest section at the top, where the gear is most spaced. A superb equation of challenge and reward”. Rewrite this in your own words guessing or finding out what the technical terms mean. What makes you think the person who wrote this enjoys climbing on rock? (quote the sections). What does she mean by “challenge and reward” in the last sentence? 3F + H 1. Fill in from the clues in the word: The story of sand and sandstone Sand is carried down a stream faster than g……..l because it is made of s……….r grains. As the grains are tumbled down a river the shape and size change as they r…b against each other and form even s……..r grains. Diamond and gold do not rub away as they are very h….d. Fossils which may later turn to oil can be trapped in the layers of sand. The layers of sand can be buried and turned into sanst….e by pressure of rocks above it. The weight presses the rock together and pushes w……r out. 21

4F + H 1. Copy and fill in the words. Deep in the earth it is very h…t. About 16km down the rocks have melted to form a liquid: molten rock is called m……a. Igneous rocks are made when magma c……s and is made s……d. B……t and gr……e are examples of igneous rocks. Metamorphic rocks are ordinary rocks that have their crystals changed by heat or pressure. Slate is made from m……e, and marble from ch….k. 2. Copy out and answer the following questions. a) The earliest type of rock formed on Earth is perhaps as old as _____________ million years. b) Copy and complete the following sentences. Sedimentary rocks may contain calcium carbonate due to their formation from

c) Two examples of sedimentary rocks are ________________ and ______________. d) The most recently formed rock-type is ___________ about __________ years ago. e) Two main factors which created METAMORPHIC rock are __________________ and __________________ acting on rock. f) Copy out and complete the following table. ROCK-TYPE

EXAMPLE

Igneous

Granite

AGE 1000-4000 Million years

Sedimentary

Metamorphic

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ORIGIN Magma cooling to form crystals

3. Match the descriptions and examples. Copy out each example and write the correct description next to the example. Examples Coal Limestone Marble Sandstone

Chalk Slate Clay Granite

Descriptions A Can be cut, carved and polished to last for a long time. B Can be shaped into blocks for building. C Can be crushed up to form foundations on roads. D Can be moulded to form pots. E Can be cut into thin ‘sheets’ for roofing. F Can be burnt to give out energy. G A sedimentary-type which may contain fossils. H If heated will release carbon dioxide as it contains calcium carbonate. I Used for buildings but will erode or ‘weather’. J Igneous type used for buildings. 5F 1. This triangle shows part of a simple rock cycle.

sedimentary

igneous

metamorphic

Copy the triangle and choose phrases from the box to put on the arrows. rocks worn away

lots of heat and squashing

rocks melt

2. What would weathering do to a stone building? 3. Describe one way in which rock can be weathered (worn away). 4. There are 3 main types or rock, what are they? 5. Describe how caves are formed. 5H 1. What is weathering? 2. Name three ways in which rock can be weathered and explain how they happen. 3. How are the following types of rock formed:a) igneous b) sedimentary c) metamorphic 23

4. Granite has bigger crystals in it than Basalt. Explain why this happens. 5. How are caves formed? 6F + H 1. Use these words and phrases to make 5 sentences: Weathering, sediment, granite, limestone, porosity, conglomerate, Sequence of events, millions of years, Igneous, metamorphic, crystals Volcano, magma, lava, erupt 2. A rock contains lots of small crystals. Did it cool quickly or slowly? Describe an experiment with salol that you did which shows that your answer is right.

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UNIT 8I

Heating and Cooling

1F 1.

Solid

Liquid

Gas

Copy out these boxes and draw how the particles would be arranged. 2. What do these words mean:evaporate condense solidify melt 1H 1. Describe in detail how the particles are arranged and how they move in a) a solid b) a liquid c) a gas 2. Copy and complete these sentences underlining the words you have added: a) When a liquid is …………………………. it evaporates and turns into a solid. b) When a ……………………. is cooled it …………………. and turns into a liquid. c) If liquid wax cools it …………………. and turns into a ………………………….. 3. Give an everyday example of i) evaporation ii) condensation iii) solidification iv) melting

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2F 1. Look at these measurements of temperature rise on heating 50ml and 100ml of water in a beaker with the same Bunsen flame, the same distance from the beaker. Time in Minutes 0 1 2 3 4 5 This is for 50ml of water. This is for 100ml of water. Time in Minutes 0 1 2 3 4 5

Temperature in degrees Celsius 25 35 44 53 60 65

Temperature in degrees Celsius 25 30 34 40 44 48

1. Do a bar chart for the top table (50ml of water). 2. Do a bar chart for the bottom table (100ml of water). 3. Look at the shape of your 2 graphs. What do they tell you about heating different amounts of water. (Hint – how hot does it get? How steep is the graph?) 2H From the tables above: 1. Do an xy scattergraph with time along the bottom axis (the x axis) and temperature along the side axis (the y axis). 2. Draw a line of best fit by hand. Do NOT just join the points do a straight line which is the best fit. 3. In terms of lines going up or down describe the shape of each graph. Use the words slope, gradient or steepness. 4. Now say what the shape of the graph tells you about how fast the water gains temperature through thermal transfer.

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3F

a) Copy the picture of the house and label all the places that heat may escape from. b) Pick two places where heat escapes and say what can be done to reduce the heat loss. 3H Do H/W 3F then:

Using some or all of the apparatus above describe a fair and reliable experiment you could do to find out what types of materials would work best to insulate the roof of a house. a) Draw a diagram of your apparatus set up. b) Say what measurements you would make. c) How would your measurements tell you which material is best? 4F 1. Whilst stirring her cup of tea with a metal spoon Naheda burnt her hand. Explain. 2. Her friend Nasrin was using a plastic spoon to stir her tea. Why didn’t Nasrin burn her finger? 3. Molecules in a hot gas are more widely spaced than the same number of molecules in a cold gas.

a) What can you say about the speed of movement of the molecules in a hot gas compared to a cold gas? b) Why is one box drawn bigger than the other for the same number of molecules? c) For the same volume, which gas, the hot or the cold, will weigh the most. Explain why? 27

4H Do H/W 4F then: 4. Why do we insulate our houses with layers of felt with air trapped in it in the roof? Use the idea of heat transfer from one place to another to explain this. 5. Hot air is rising above a lit candle – why does the hot air rise? 6. What is the difference between a smoke particle and a carbon dioxide molecule in a candle flame? Do they both move upwards and if so why? 5F 1. Copy these out and match them to the correct temperatures. Body temperature Oo C Centre of Sun 30oC Freezing ice 14 000 000oC Boiling water 37oC A hot day 100oC 2. Look at these pictures and their surrounding temperature. Say which objects will gain heat and which will lose heat.

5H 1. Copy out the sentences below using the correct temperature from the box. -18oC

Oo C

4oC

30oC

37oC

100oC

900oC

14000000oC

a) The human body remains at a constant temperature of ___________________ oC b) _____ oC is the boiling point of pure water. c) H2O freezes at _______ oC d) The temperature at the centre of the sun is about _________________ oC e) A freezer keeps food at about __________ oC f) On a hot summer’s day the air may be at ________ oC g) A fridge keeps food at about ________ oC h) A Bunsen burner is about _________ oC 2. a) Which has more heat in it; a cup of boiling water or a swimming pool of water at 30oC. b) Explain your answer.

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6F + H

Revision

1. Find and read all your class notes and homeworks on heating and cooling. 2. Draw a temperature line like the one below and along it write at least 5 things at the right temperature along the line. -30oC

0 oC freezing water

30oC

60oC

90oC

120oC

150oC

180oC

3. Write a sentence to explain why/how each of these happen: a) heat conduction b) expansion c) heat convection 4. Write 10 questions and answers about something in your notes. Get someone to test you on the answers.

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UNIT J

Magnets and Electromagnetism

1F 1. a) Copy the bar magnet, then draw the magnetic fields around it. N

S b) Write down what we mean by ‘magnetic field’. 2. For the magnets shown below state whether they will attract or repel.

3. The drawing shows a magnetic material being attracted to a bar magnet.

a) What is the magnetic pole at point A? b) Explain why the magnetic material is attracted to the bar magnet. 1H Do 1F then: 4. a) Which diagram shows the magnetic field of a bar magnet?

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b) Which diagram shows a pair of magnets that attract each other?

c) The diagram shows the magnetic field pattern near one end of a magnetised steel bar. The circle represents a small compass placed near the steel bar.

Copy the diagram then draw an arrow inside the circle to show which way the north-seeking pole of the compass points. 2F + H 1. Copy and draw the magnetic field around this bar magnet. Draw in arrow Z to point to the strongest part of the magnet.

2. Draw a picture of an electromagnet. 3. How can you make an electromagnet stronger? 4. Give one use of an electromagnet. 5. Why can electromagnets sometimes be better than permanent ones? 3F 1. The pictures below show 6 experiments with bar magnets and various materials. For each experiment, there is attraction, repulsion or no magnetic forces acting. Write down your answer for a) - f) as attract, repel or none.

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2. Copy the list of materials, then tick the ones that are magnetic and put a cross beside the ones which are non-magnetic. Iron Nickel Plastic Steel

Brass Copper Wood Gold

Silver Leather Aluminium Sulphur

3. Copy and complete the sentences about magnets using the words in the box. field

south

stronger

attract

two

seeking

poles

south

repel

Any magnet has __________ oppositely behaving ends called __________. If the magnet is left to spin freely, it will stop pointing in a north-_____________ direction. The end pointing north is called the north-___________ pole. The other end is called the __________-seeking pole, or south pole for short. Opposite poles ____________. Similar poles _______________. The area around a magnet is known as the magnetic ____________. The stronger the magnet, the __________ the field. 3H Do 3F then: 4. Denise has a problem to solve. She has two magnets that do not have the poles marked on them; Magnet 1 and Magnet 2. Magnet 1 has a blue end and a red end. Magnet 2 has a yellow end and a purple end. She holds the ends of the magnets together to see if there is an attraction (A) or a repulsion (R). She records her results in the table below. Part of the results table is filled in. Copy and complete the rest for her. End of Magnet 1 RED RED BLUE BLUE

End of Magnet 2 PURPLE YELLOW YELLOW PURPLE

4F + H Write up electromagnet practical as per teacher instruction.

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Force A

5F 1. Two pictures of a scrap yard electromagnet a) and b) are shown below.

Write down which of the circuits below, Circuit 1 or Circuit 2 is needed to operate the electromagnet in each case.

2. Look at this picture of an electric bell circuit.

Copy then use the words in the box to complete the description of what happens when someone presses the switch. off down up open made closed broken open When the switch is ________ the electromagnets turn on. The iron bar is pulled ________. This clangs the gong. At the same time the contact is ___________. The magnets go ________ and the arm springs back, ready to start again. 3. Copy and circle the correct words in the brackets to complete these sentences about electromagnets. a) An electromagnet will be stronger if the current through it is (higher / lower). b) An electromagnet will be stronger if there are (fewer / more) turns on the coil. c) An electromagnet will be stronger with a core made of (iron / wood / copper). 5H Do 5F then: 4. a) The diagram below shows a circuit breaker. Use the words in the box to put names to parts a) to e) pivot brass contacts spring iron core

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iron rocker

c) Rearrange the sentences in the correct order to explain how the circuit breaker works. i) They break the circuit if the current is too high. ii) Now it has to be reset manually. iii) As the iron rocker moves, the contacts separate, the switch is tripped, and the spring flips past the rockers so that the switch is held open. iv) Circuit breakers are fitted to the incoming live wire and v) It does this because a large current allows the electromagnet to attract the iron rocker, despite the spring. 6F + H 1. Read through class notes. 2. Draw things to show magnets attracting / repelling. 3. Describe how an electromagnet can be made and give one use of it. 4. List the three magnetic elements.

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UNIT K

Light

1F Copy this diagram into your book and draw light rays from the light source to show how a shadow is on the screen. Label the shadow.

2. Describe how shadows are made using your diagram to help you. 1H Do 1F then: 3.

a) Draw these circles into your book. b) Label them Moon, Earth and Sun. c) Draw rays to complete the diagram to show how an eclipse is formed. d) Explain in your own words how an eclipse is formed. Use the diagram to help you. 2F window

tracing paper

black card

opaque

translucent

transparent

1. Copy out these sentences putting the correct word from the box in the space. Some words will be used twice. a) _______________ objects let all the light through without absorbing any. An example of this is a ________________. b) This material only allows some light through. We call this material ____________ and an example is ______________. c) Materials which let no light pass through are called ______________. An example is __________________. d) Clear plastic is _______________________. e) Bathroom windows are often made of frosted glass. These windows are ____________.

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2H Do 2F then: 2. Copy the diagram below and show the path of a light ray so that the boy can read the book.

3. Describe how the light helps the boy to read the book. Use the word reflect in your description. 3F 1. Copy these diagrams and draw what happens to the light when it hits each mirror. (remember to put in arrows to show the direction of light).

2. Which angles are the same? Copy the diagrams and fill in the missing letters.

3H Do 3F and then draw a diagram to show how a periscope works.

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4F 1. The diagram shows light rays about to be reflected from a smooth surface.

a) Copy and complete the diagram to show how the light rays are reflected from this surface. b) Name a type of reflector with a smooth surface. 2. The diagram shows light rays about to be reflected from a rough surface.

a) Copy and complete the diagram to show how the light rays are reflected from this surface. b) Most reflectors have rough surfaces. Give 2 examples of a reflector with a rough surface. c) What type of reflection would you get from a piece of sand paper? 3. List 3 uses of mirrors. 4H Do 4F then: 1. In physics what is a medium? 2. When light enters glass from air it changes direction. What is this change of direction called?

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3. Glass is denser than air so light will refract when it enters and leaves a glass block. The diagrams show rays of light in air entering a glass block. For each one copy and complete the path of the ray of light into and out of the block.

4. Copy the sentences, then circle the correct word in the brackets to complete them correctly. a) When a light ray travels from one medium into another, more dense, medium, it bends (away from / towards) the normal. b) When a light ray travels from one medium into another, less dense, medium, it bends (away from / towards) the normal. 5F 1. When white light passes through a prism it is split up into different colours. a) What is the name given to this ‘splitting up’ of white light; reflection, refraction, absorption. The picture below shows white light passing through a prism and landing on a white screen.

b) What is the name for the ‘rainbow of colours’ produced; spectrum, bending, shade, range. c) Write down the seven colours you would see on the screen from the list below: magenta yellow indigo pink red blue gold cyan violet black green orange d) Which colour light bends most; blue light or red light?

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H5 Do 5F then: 2. The drawing shows a red filter. The red filter produces red light. Explain how it does this.

3. The drawing shows a red filter followed by a blue filter.

a) What colour will be seen on the screen? b) Explain your answer. 4. Abi is going to the spectrum disco. She’s wearing a green top with blue spots and red trousers. She wanders from the blue room to the green room to the red room. What colour will her outfit appear in each room?

6F + H

Revision

1. Write down these words and their meaning. luminous transparent translucent reflection refraction spectrum 2. Learn your ray diagrams and how a periscope works. 3. Read through all your other notes.

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opaque

UNIT 8L

Sound and Hearing

1F 1. What type of sound would these things make? (high, low, loud, quiet) base drum, whistle, triangle, fog horn, scream, thunder, squeak, whisper, 2. Try to think of one more example for each type of sound. 3. What vibrates to make the sound in the following instruments. a) violin b) trumpet c) triangle

1H Do 1F then: 4. What can you do to a vibrating string to make the note lower? 5. What would happen to the note if the string was thicker? 2F 1. The diagrams below show 4 traces of sound waves on a Cathode Ray Oscilloscope. Copy them into your book and use the letters A, B, C or D to answer the questions.

a) Which sound is the loudest? b) Which sound has the highest pitch? c) Which sound has the smallest amplitude? d) Which sound has the lowest frequency? 2. On trace A draw the same sound but quieter. 2H Do 2F then: 3. Sound waves can be displayed on an oscilloscope screen like the one below. Copy the diagrams into your book and answer the questions.

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bang,

a) Which of the lines in the picture indicates the amplitude of the wave? b) A wave with the same frequency but carrying more energy than the first one is fed into the oscilloscope. i) Draw how the wave will look on screen 2. ii) What difference would you hear? 3F + H 1. The following statements are all about sound. Copy the ones that are correct into your book. Sound is a form of energy. Sound travels faster than light. Sound can travel through a vacuum. Humans can hear all sounds. Sound needs a material to travel through. Loud sounds damage our hearing. All sounds are caused by vibrations. We hear sounds because our ear drum vibrates. The loudness of a sound depends on the amplitude. The pitch of a sound depends on amplitude. The loudness of a sound depends on the frequency. Sounds cause the substance they are travelling through to vibrate. 2. The picture shows a demonstration of sound travel using a bell jar.

a) Copy out the sentences and underline the correct word in the brackets. When air is sucked out of the jar the ringing of the alarm clock inside the jar gets (louder / quieter). When all the air is removed the bell (can not be heard / stops). b) Copy out the sentence and complete with the correct statement. The ring of the alarm clock goes quiet because: there is no air in the jar to carry the vibrations sound can not travel through the glass of the bell jar the vacuum stops the bell moving

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4F 1. The table below is incorrect. Draw the table and put the ear part with its correct job. EAR PART pinna ear drum balance canals small bones nerve

JOB carries message to brain makes the sound louder collects sound waves keep us steady a skin which vibrates

2. The bar chart shows the range of frequencies that people and animals can hear at.

a) Who has the most limited range of hearing? b) Suggest a reason why dolphins need to hear such high frequency sounds. c) Underline the correct words to complete the sentence: Dolphins can hear higher frequency sounds than dogs. This means that dolphins can hear sounds of a (lower pitch / higher pitch).

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4H Do 4F then: 3. Sound levels are measured in decibels (dB). The graph shows the recommended maximum times people should listen to sounds of different levels. At longer times there could be serious damage to hearing.

a) What is the maximum time each day for listening to a personal stereo at 96 dB? b) In what way could a sound of more than 120 dB damage the ear? c) i) Sally works for five hours in a nightclub. What should the maximum level be in the nightclub so that her hearing is not damaged? Use the graph to find the answer. ii) How can ear plugs protect Sally’s ears? 5F + H 1. Read through your notes. 2. Copy out the parts of the ear and say what each part does. 3. Learn the speed of sound and light. 43

4. Learn these words and their meanings: amplitude wavelength hertz decibels frequency

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