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Ideas about Energy and Forces
1. Identify a situation in which the following forms of energy are found:
(a) Kinetic anything moving, eg: person running, car driving
(b) chemical potential battery, food
(c) gravitational potential anything above the ground eg: top of a slippery-dip
(d) elastic potential anything stretched eg: bow and arrow, stretched rubber band,
compressed spring
(e) heat heater, light globe
(f) sound trumpet, voice
(g) light light globe, sun
(h) electrical light globe, battery, power point
(i) nuclear uranium atom, nuclear power plant
2. State the law of conservation of energy
Energy cannot be created or destroyed; it can only be transferred or transformed.
3. Light globes are only 5% efficient. Explain what happens to the rest of the energy in the
light globe.
The rest of the energy is converted into heat energy.
4. Describe the energy transformation and transfers involved in a car crash. Identify which
are transfers and which are transformations.
Transfer of energy: as one car collides with the second car, it transfers its kinetic energy
to the second car.
Transformation of energy: the kinetic energy of the car is transformed into heat, light,
sound and elastic potential in the crumpled part of the car.
5. Identify a device which involves the following energy transformation:
(a)
(b)
(c)
(d)
Electrical to sound microphone
Electrical to light light globe
Chemical potential to kinetic battery operated car
Kinetic to heat. Rubbing hands together
6. Define the word “force” in a science context.
A force is a push, pull or twist
7. Identify 3 non-contact forces.
Gravity, magnetism, electrostatics
8. Use the term “field” to describe what happens when you put a nail near, but not
touching, a magnet.
The magnetic field of the magnet extends past the magnet itself. When the nail is in the
magnetic field, it experiences a force due to the magnet. It is attracted and moves
towards the magnet until it sticks to the magnet.
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9. Identify four effects a force can have.
Stop motion, start motion, change the direction of motion, deform an object.
10. Draw a scientific diagram of an electrical circuit that includes a battery, light globe and
switch. Label it with the energy transfers and transformations involved.
Battery transforms chemical energy into electrical energy
Kinetic energy of electrons
transferred to other electrons
Light globe transforms electrical energy to light and heat energy
11. Explain why astronauts can see each other in space, but not hear each other unless they
have a radio.
Light does not need a medium such as air to travel through it and so astronauts can see
each other.
Sound needs a medium to travel through. Sound is transmitted by the vibration air
particles. Since there is no air in space, the sound cannot travel, so astronauts cannot
shout to each other.
In space astronauts use radios to communicate with each other. Radio waves do not
require a medium to travel so information can be relayed between the astronauts and the
space shuttle. However, to hear the information a medium is required. Astronauts have
air in their space suits so that when the radio waves are converted into sound waves they
can hear them.
12. Identify a situation in which heat is transferred by:
(a) Conduction stove to saucepan
(b) Convection movement of hot air above the sea
(c) Radiation movement of heat away from a heater.
13. Define the term “friction”
When two objects are rubbing against each other, friction is the force that opposes the
motion
14. Identify a situation in which friction is useful
Helping you walk without slipping, keeping a car on the road, writing
15. Identify a situation in which friction is annoying
Machine parts rubbing against each other produce heat, wearing down of car tyres
16. Explain, rubbing a balloon as an example, how electrostatic forces are produced.
Electrostatic forces are produced when electrons are rubbed off or onto an object. For
example when a balloon is rubbed with a cloth, the electrons may be rubbed from the
cloth onto the balloon. Since the balloon had an equal number of electrons to start off
with, rubbing electrons onto it will make it negative. This means it will be
electrostatically charged and can attract or repel other charged objects and attract small
uncharged objects such as hair. This is an electrostatic force.
17. Identify two other situations in which an electrostatic force is present.
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Photocopiers, sparks when you rub your feet on carpet and touch a metal object
18. Describe what you would observe if you rub two Perspex rods with a cloth and bring one
close to the other. Explain why it happens
The rods would move away from each other. This is because the rods have the same
electrostatic charge and like charges repel.
19. Describe what you would observe if you rub one Perspex and one ebonite rod with a
cloth and bring them close to each other. Explain why it happens.
The rods would move toward each other. This is because the rods have opposite
electrostatic charges and opposite charges attract.
20. Describe one everyday situation in which electromagnets are used.
Car yard - to move cars from one place to another
Stereo speakers
21. Describe what you would observe if you brought two North or two South poles of a
magnet close to each other.
The magnets would move away from each other, they would repel each other
22. Identify three everyday situations in which magnets are used.
Keeping objects on the fridge, in electrical devices such as loudspeakers, holding
refrigerator and kitchen doors closed.
23. Define the term “gravity”.
The force of attraction between any two objects due to their mass.
24. A student said that she was attracting the pen on her desk towards her. Was she correct?
Explain your answer.
Yes: all objects exert a force of gravity on each other, but in the case of the pen, the
person is so small and the attraction of the pen to the Earth is so much greater (due to the
Earth’s greater mass) that the attraction cannot be detected.
Ideas about the Structure of Matter
25. State the Particle Theory of Matter
All matter is made up of small particles. These particles are always moving and their
movement determines some of the properties of the object. The energy and range of
motion of particles in a gas > liquid > solid.
26. When you heat up a piece of metal it expands. Explain this in terms of the Particle
Theory.
The particles in the metal are vibrating in their place. As they heat up, the particles
move faster and require more space to move in, so they move apart from each other.
This makes the piece of metal expand.
27. Describe the position and movement of the particles in a
(a) solid The particles are packed tightly together and vibrating in their places.
(b) liquid The particles are packed tightly together and slide over one another
(c) gas The particles are spaced apart from each other and are moving quickly around.
28. Explain the following in terms of the Particle Theory”.
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(a) Solids keep their own shape, whereas liquids and gases take the shape of the
container
The particles in solids are held tightly together and can only vibrate in their place, so
the solid keeps its own shape. In liquids and gases, the particles are able to move
around and so they take the shape of the container.
(b) Solids and liquids have a constant volume whereas gases take the volume of the
container
The particles in solids and liquids are as close together as they can get. They cannot
move further apart so they have a fixed volume. In gases, the particles are held less
tightly so can move around to fill the container completely, so gases don’t have a
fixed volume.
(c) Solids cannot be poured whereas liquids and gases can.
The particles in solids are held tightly together and can only vibrate in their place,
they cannot slide over each other. In liquids and gases, the particles are able to
move around and so they can roll over one another and be poured.
29. Explain in terms of the Particle Theory why balloons get larger and eventually pop when
they are heated up.
The particles in the gas in the balloons heat up. This means that they move faster and
collide with the sides more often, making the pressure inside the balloon greater. This
makes the balloon larger. If the balloon gets too large, the rubber cannot take the
pressure and breaks so the balloon pops.
30. Lead is more dense than gold.
(a) Describe what you would observe if you compared 1 cm3 of lead with 1 cm3 of
gold. The lead would be heavier than the gold.
(b) Explain this observation in terms of the Particle Theory. The lead has more
particles packed into the same amount of space. Since density is the mass over
the volume, if you keep the volume the same but increase the number of
particles, the object gets heavier.
31. When you heat water up it turns into vapour. Describe what is happening to the particles
in the water as you heat it up.
The particles gain energy and move faster. The forces between them get less able to
hold them together. Eventually the particles separate from each other and are able to
move around quickly. Thus it changes from a liquid into a gas.
32. When you cool water down it turns into ice. Describe what is happening to the particles
in the water as you cool it down.
The particles are losing energy and so are moving more slowly. The forces between the
particles is able to hold them together more, so they become closer to each other, and
eventually fixed in place. Thus they change the sample from a liquid into a solid.
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33. Draw a diagram to show the relationship between the following changes of state and the
energy transfers involved: melting, freezing, condensation, evaporation and boiling.
Gas
evaporation
condensation
Heat put in
Heat released
Liquid
melting
freezing
Solid
34. Describe how you could tell the difference between metals and non-metals using their
observable characteristics.
Metals
Conduct heat
Conduct electricity
Shiny
Malleable and ductile
Non-metals
Don’t conduct heat
Don’t conduct electricity
Dull
Brittle
35. Identify the names and symbols of the first 20 elements on the Periodic Table, as well as
the symbols of gold, silver, mercury, copper, lead, iron.
See the Periodic Table.
36. Identify 4 common mixtures
Air, milk, sea water, orange juice…
37. Describe, using examples, the importance of water as a solvent.
Water dissolves a large range of things so it is important such things as personal hygiene,
dissolving chemicals in our cells so that our biochemistry can take place, dissolving
minerals in water systems. It also is essential for dissolving oxygen in aquatic/marine
systems.
38. Define the terms solute, solvent and solution.
Solute: the substance that is dissolved to make the mixture
Solvent: the substance that the solute dissolves in. Solvents are often liquids.
Solution: the mixture of solute and solvent.
39. Identify a situation in which we would separate a mixture using:
(a) Filtration: Insoluble solid in liquid eg: sand in water
(b) sedimentation Insoluble solid in liquid eg: sand in water
(c) sieving Insoluble solid in liquid eg: sand in water
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(d) distillation Separation of a solution when you need the solvent eg: getting
purified water from seawater. Or for separating a mixture of liquids with
different boiling points.
(e) Chromatography Separating colours in dyes for analysis
(f) evaporation Separation of a solution when you need the solute eg: getting salt
from seawater.
(g) Condensation Distillation to get the water out of salt water uses condensation.
The water vapour is cooled by the condenser. It condenses and becomes a liquid
again.
(h) Crystallization Separating two solids with different solubilities
(i) magnetic attraction Separating iron from anything else.
40. Explain the difference between elements and compounds, including a diagram
Elements contain only one type of atom:
or
Compounds contain two or more elements chemically combined:
41. Describe three things you might observe if a chemical reaction takes place
A new substance is formed. You can infer this by observing: a change of temperature,
change of colour, production of a gas or a solid, a sound given off, light given off.
42. Explain the difference between compounds and mixtures, including an example of each.
A compound is composed of two or more elements chemically bonded together. The
elements in a compound cannot be separated by physical separation techniques. On the
other hand, a mixture is composed of two or more substances (elements and/or
compounds) mixed together but not chemically bonded together. They can be separated
by physical separation techniques. To represent these using particle diagrams:
Mixture: O O ⌂ █ ▼ ▲ ▲ ▲ ⌂
Compound:
O-▼
O-▼
O-▼
O-▼
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Ideas about Living Things
43. Describe the Cell Theory
All living things are made of cells. All cells come from other cells.
44. Describe the function of the following cell parts: nucleus, cytoplasm, cell membrane,
cell wall, chloroplast
Nucleus: controls the cell’s function / contains genetic information
Cytoplasm: fills the cell and allows chemical reactions to take place
Cell Membrane: semi-permeable so controls the movement of chemicals into and out of
the cell
Cell wall: provides support for plant cells
Chloroplast: provides a site for photosynthesis.
45. Draw a diagram of a plant cell, including the parts in q44.
Nucleus
Chloroplast
Cell Wall
Vacuole
Cell membrane
46. Identify the substances that move in and out of cells and what they are used for.
Into: water, used for chemical processes and to dissolve some chemicals. Also to fill the
cell. Oxygen, used for respiration to make energy. Glucose, used for respiration to
make energy. Other chemicals (amino acids) are used to build the proteins for the cells.
In plants, carbon dioxide and water to photosynthesize.
Out: water, carbon dioxide as wastes from respiration. In plants, oxygen as waste from
photosynthesis. Also other chemicals such as urea.
47. Identify the difference between unicellular and multicellular organisms
Unicellular are one cell only whereas multicellular organisms are made up of a number
of cells, organized to form the organism.
48. Describe the physical features that scientists use to classify vertebrates.
Vertebrate type
Covering
Method of birth
Mammals
Reptiles
Amphibian
Bird
Fish
Fur or hair
Dry scales
Slimy skin
Feathers
Scales
Live
Lay eggs
Lay eggs
Lay eggs
Lay eggs
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Method of
breathing
Lungs
Lungs
Lungs/gills/skin
Lungs
Gills
Endo or ecto
therm
Endotherm
Ectotherm
Ectotherm
Endotherm
ectotherm
49. Define the term micro-organism
Organism too small to be seen with the naked eye.
50. Identify three beneficial effects that that micro-organisms have on living things and the
environment
Decompose waste. Provide digestive assistance. Make some products such as yoghurt
and bread
51. Identify two harmful effects that micro-organisms have on living things and the
environment.
Make food go off. Cause some illnesses
52. Describe briefly how unicellular organisms reproduce
Unicellular organisms reproduce by mitosis. This means that one cell copies itself and
splits into two daughter cells.
53. Explain the relationship between cells, tissues, organs and systems in multicellular
organisms.
Cells are the basic building blocks of living things. Identical cells group together to
form tissues, which make up the structure of organs. Organs are large parts of the body
which perform particular functions. Organs which work together make up a system, for
example the digestive system.
54. Explain why multicellular organisms need organs and systems
There are many processes in multicellular organisms the require complicated steps. Each
step is accomplished by a particular organ. These organs, put together, perform a task
which is required by the multicellular organism in order to get and use energy, grow and
develop, respond to stimuli and reproduce.
55. Write a word equation for respiration and explain what it is used for
Oxygen + glucose  carbon dioxide + water + energy
This process is used to produce the energy the body needs to move and for chemical
processes to take place.
56. Write a word equation for photosyntheses and explain what it is used for
light energy
Chlorophyll
carbon dioxide + water

Oxygen + glucose
It is used to produce glucose for the plant to use for respiration.
57. Describe the role of the root, stem and leaf in a flowering plant.
Root collects nutrients including water from the soil. Stem transports nutrients to other
parts of the plant and provides a structure for the other parts. Leaf is the site of
transpiration, and photosynthesis.
58. Describe the role of the following systems in the human body:
(a) digestive breaks food down into parts that can be absorbed for use by our body.
(b) Circulatory moves blood around the body so oxygen can be supplied to all parts
of the body and carbon dioxide can be removed.
(c) Excretory cellular waste is removed by this system
(d) Skeletal provides structure for the organism
(e) Respiratory provides oxygen and removes carbon dioxide
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Ideas about the Universe and the Earth
59. Write the following in order of size, from largest to smallest: Earth, Sun, Moon, Jupiter,
asteroids.
Asteroids, Moon, Earth, Jupiter, Sun
60. Everything in our Solar System moves. Describe the movements of the objects in q 59.
The Earth, Jupiter and asteroids all move in an elipse around the Sun. The moon moves
around the Earth. All of the objects also turn on their axis.
61. Explain how we get night and day
The Earth turns on its axis once every 24 hours. The part of the Earth that is pointed
towards the Sun has day and the other half has night.
62. Explain how we get seasons
The Earth is tilted on its axis. As it moves around the Sun, one part of the Earth gets a
greater concentration of sunlight which makes it summer in that part. The opposite par
of the Earth has winter at that time. Areas in between experience autumn and spring.
63. Define the following terms:
(a) Universe All of the observable things that exist.
(b) Galaxy An organization of gas stars and dust. Most galaxies move together as
one system
(c) Solar system Group of objects orbiting one star (or a pair of binary stars)
(d) Planet Object of a certain size and mostly spherical shape which orbits a star.
(e) Star Ball of gas which gives off light and heat due to the process of fusion
(f) Nebula Cloud of dust and gas – birthplace of stars
(g) Moon rock which orbits another heavenly body.
64. Draw a diagram of the Earth and label the core, mantle, crust and lithosphere.
65. Identify the gases that make up air and explain the difference between Earth’s
atmosphere and space
Air is 78% nitrogen, 21% oxygen and the other 1% is mostly made up of argon, with a
small amount of other gases, such as carbon dioxide. Space has no air in it.
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66. Explain why the ozone layer is important to life on Earth
The ozone layer blocks most of the UV radiation coming from the Sun. This is
important as high levels of exposure to UV light can cause sunburn, cancers, destruction
of trees and plants.
67. Explain why greenhouse gases are important to life on Earth
Greenhouse gases trap some of the heat from the Sun, making the Earth a good
temperature for life to exist. Without the greenhouse gases, the temperature on Earth
would be much colder.
68. Draw a diagram of the water cycle and label all of the processes involved.
69. Explain how the moon affects the tides.
Because the Moon is matter, it exerts a force of gravity on the objects around it. The
water on the surface of Earth is pulled towards the Moon, which is what we see as a high
tide. The rotation of the Earth causes the water to spill out over the shore when the
gravity of the moon is forced to release that particular section of ocean.
70. Describe how the Sun affects tides.
The Sun affects tides for the same reasons as the Moon, but since the pull of gravity
depends on distance and the Moon is much closer to the Earth, the Sun has less effect.
When the Sun and Moon are lined up relative to the Earth, we get particularly large tides
called Spring tides. When they are at right angles to each other, we get particularly
small tides called Neap tides.
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71. Define the term “mineral”
A naturally occurring substance that has a definite chemical composition (it is an
element or compound). They are generally solid and crystalline. They are the building
blocks of rock.
72. Rocks get broken down in both chemical and physical ways.
(a) Describe two physical processes that break down rocks.
Wind blowing across the rock, water running down the rock, water freezing in cracks
and expanding, extreme temperature changes.
(b) Describe one chemical process that breaks down rocks.
Water containing mild acids react with chemicals in the rock and break it down
73. Define the terms weathering, erosion and deposition and explain how these affect the
land.
Weathering is the breaking down of rocks due to physical and/or chemical processes.
Erosion is the carrying away of broken bits of rock by wind and water. Deposition is the
putting down of the bits of rock in a different place to where they came from.
Weathering and erosion make large bits of rock, for example cliffs and mountains, wear
away to sediment. Deposition builds up sediment to eventually form new bits of rock.
74. Draw a diagram of the rock cycle.
Ideas about the Environment and Ecosystems
75. Describe an animal that has adapted to its environment. Explain how the adaptations
help it to survive.
Pick an animal! For example, a giraffe has a long neck and long legs. These help the
giraffe to get leaves from the tops of trees so they have lots to eat. OR Dolphins have a
streamlined shape that allows them to swim through the water with very little friction.
76. Describe a plant that has adapted to its environment. Explain how the adaptations help it
to survive.
For example, a cactus has thorns and stores water inside. The thorns protect it from
predators and water storage prevents dehydration of the cactus in dry times.
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77. Define the terms producers, consumers and decomposers.
Producers are organisms which make their own food through photosynthesis.
Consumers are organisms which eat other organisms (either producers or other
consumers). Decomposers are organisms which break down dead organisms.
78. Draw a food web that contains two Australian producers, consumers and decomposers.
79. Discuss some effects of bushfires, drought and flood on Australian ecosystems.
Bushfires can destroy large parts of bushland. On the other hand, fire is needed for some
Australian plants to regenerate. Drought and flood both destroy ecosystems.
80. Explain the difference between natural and made resources.
Natural resources are useful substances found in the environment. They include things
like salt, water, minerals. Made resources are materials which are made by humans such
as paper, plastic and concrete.
81. Describe examples of resources from:
(a) living things wool, cotton, food
(b) the air oxygen, nitrogen
(c) the Earth minerals, coal, metals
(d) the ocean oil, food, salt
82. Identify the three fossil fuels and describe a use of each
Coal: used to produce electricity
Oil: used to produce petrol, kerosene, plastic and some pharmaceuticals
Gas: use for heating and cooking.
83. Identify three renewable and three non-renewable sources of energy.
Renewable: wind power, tidal power, biogas
Non-renewable: fossil fuels, nuclear
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