Unit 2 Ecosystems, Our Universe and...
Transcript of Unit 2 Ecosystems, Our Universe and...
SNC2L Unit 2 – Ecosystems, Our Universe and Chemistry
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Unit 2 – Ecosystems, Our Universe and Chemistry
Lesson 6: Ecology and Ecosystems
Lesson 7: Biomes
Lesson 8: Why do we study Space
Lesson 9: Our Solar System
Lesson 10: Atoms
Note to Student: Read each lesson and then do all the assignments and when you are finished
hand in each lesson for marking.
UNIT 2 GLOSSARY OF TERMS
ATOMS
atom: smallest particle of a type of matter that has all of the same
characteristics as that type of matter.
electron: a part of the atom that has a negative electrical charge; orbits the
nucleus
neutron: a part of the atom that has neither a positive or a negative charge; is
found in the nucleus.
nucleus: central part of an atom, which contains neutrons and protons
proton: a part of the atom that has a positive charge; is found in the nucleus
ECOLOGY
biomes: large region of the earth that has characteristic kinds of organisms
biosphere: thin zone of the earth that supports all life
community: all the organisms living in a certain area
conservation: wise use of natural resources
consumers: organisms that get food by eating other organisms
decomposers: organisms that feed on dead organisms
ecology: study of the relationship between living things & their environment
ecosystem: all the living things and nonliving parts of an environment
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evolution: process by which organisms change over time
extinct: organism that no longer exists on earth
habitat: place where an organism lives
natural resources: materials and energy in the biosphere used by living things
niche: an organism's role, or job, in its environment
nonrenewable resources: resources that cannot be replaced
pollutants: harmful substances
pollution: anything that harms the environment
population: all the members of one species that live in the same area
producers: organisms that can make their own food
renewable resources: resources that can be replaced by nature
UNIVERSE
asteroids: large chunks of rock that orbit the sun
astronomer: scientist who studies heavenly bodies
astronomy: study of heavenly bodies
dehydrated: an item in which water has been removed
environment: the surroundings that living things live in
galaxy: large group of stars
gas giants: planets that are large and primarily composed of gases
gravity: force of attraction that exists between all objects in the universe
inner planets: the four planets closest to the sun
light-year: the distance that light travels in one year
meteorite: piece of rock or metal that hits the earth's surface
meteoroid: piece of rock or metal that orbits the sun
Milky Way galaxy: the galaxy in which the sun is located
North Star: Polaris, the star above the north pole
orbit: curved path of the one object around another object in space
satellite: natural or artificial object orbiting a body in space
space probe: a machine sent from Earth to study other objects in space
Space Shuttle: reusable space vehicle
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telescope: instrument to gather s and magnify light to study the heavens
terrestrial planets: planets that are similar to Earth in their size and composition
tide: daily change of the level of ocean water
universe: everything that exists
waning: after the full moon; as the visible part of the moon decreases
waxing: after a new moon; as the visible part of the moon increases
Lesson #6: What is Ecology?
What is ecology?
Our planet is huge. It has an area of more than 500 million square kilometers (200 million square
miles). Yet life exists only on its surface, and slightly above and below. We call this narrow zone
of life the biosphere. You may know that the term "bio" means “life”.
The biosphere is full with all kinds of life. These organisms live in all kinds of environments.
Everything that surrounds an organism makes up its environment. Living things are affected by
their environment. They can also have an effect on their environments.
The study of the relationship between living things and their environment is called ecology.
Scientists who study ecology are called ecologists. The living and nonliving parts of a specific
environment make up an ecosystem. Some of the nonliving parts of an ecosystem are air, water,
sunlight, and soil. Living things need these things to survive.
An ecosystem can be large, like an ocean or jungle. Or it can be small, like a pond or a patch of
grass in an empty lot. Even a home aquarium is an ecosystem!
Each ecosystem is made up of one or more communities. A community is all the organisms
living in a certain area. For example, a pond community may include frogs, fishes, and water
lilies.
Members of a community depend upon each other. They also depend upon nonliving things like
air, light, and water. The living and nonliving parts of the environment are always interacting.
And a change in one part can cause a change in all the parts.
Each community is made up of populations. A population is all of the living things of the same
species living in the same area. How many students make up the population of your class?
What are some other characteristics of an ecosystem?
If someone asked you where you live, how would you answer? The place where an organism
lives is its habitat. A habitat is a special place. It provides all of an organism’s needs, like food
and air. It provides an organism with shelter. It also provides a place to reproduce. Sometimes,
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different species share the same habitat. For example, insects and mushrooms may share the
same rotting log. Birds, squirrels, and insects might live in the same tree.
Now suppose someone asked what your role or job in life is. You would probably say that you
are a student. Being a student is the job or role that you do where you live. Organisms also have
jobs and roles in their communities. The job of a living thing is called its niche.
Living things may have the same habitat but they do not have the same niche. For example,
tigers and deer both share a habitat in Asia. But while tigers chase and eat deer-deer eat grasses.
They do not have the same role.
Although the tigers and deer in Asia have different related by how they get their food. Each
ecosystem is made up of different kinds of organisms.
Some are producers. Producers can make their own food. On land, the main producers are
plants. In lakes and oceans, algae are the main producers.
Others are consumers. Consumers get food by eating other organisms. Some consumers eat only
plants (plant eating consumers). Others eat meat, or other animals (meat eating consumers).
And some, like people, can eat both plants and animals.
Some animals feed upon dead animals. They eat animals that have died or that have been killed
by other animals. For example, vultures eat dead animals.
Bacteria break down the wastes or remains of organisms. They are decomposers. Decomposers
return materials from dead organisms to the soil.
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Assignment #1: Studying Ecosystems
ECOSYSTEM
Figure A shows a lake ecosystem. The parts of this ecosystem are listed below. Next to each
part shown in the Table, indicate with a mark if the item is living or non-living.
No. ITEM (8 marks) LIVING NON-
LIVING
1 sunlight
2 catfish
3 weeping willow tree
4 raccoon
5 heat
6 water
7 sunfish
8 water plants
9 frog
10 muddy lake bottom
11 air
12 insects
13 bird
14 bacteria, algae and other one-celled organisms
(not shown but always present in a lake ecosystem)
15 Why are one-celled organisms not shown?
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FILL IN THE BLANK
Complete each statement using a term or terms from the list below. Write your answers in the
spaces provided. Some words may be used more than once. (8 marks)
living and non-living biosphere community
ecology environment
1. An ecosystem is made up of both things.
2. All living members of an ecosystem make up a .
3. The region of Earth where life exists is called the .
4. All of the living and non-living parts of an organism’s surroundings are called its
.
5. The study of the relationship between organisms and their environment is called
.
6. Do living things affect non-living things? (yes, no)
7. Do non-living things affect living things? (yes, no)
8. A change in one part of an environment causes a change in another
part of the environment. (can, cannot)
FOOD CHAINS
Look at Figure A. It shows a food chain. The arrows in the food chain show the direction that
food moves along in the chain.
Figure A
Living things depend upon each other for food. Every living thing is a link in a food chain. A
food chain shows the order in which living things feed upon other living things.
Not all organisms eat the same kinds of food. Therefore, there are many different food chains.
But all food chains begin with PRODUCERS. WHY? (1 mark)
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Why is the sun the source of energy in an ecosystem? (2 marks)
FINDING THE MISSING LINKS IN THE FOOD CHAINS
Six food chains are shown below. One link has been left out of each chain. Identify the
organism that is missing. In the chart below, indicate your answer by placing a mark in the
appropriate column. (6 marks)
Food
Chain Item Producer
Plant Eating
Consumer
Meat Eating
Consumer
1 a.
2 b.
3 c.
4 d.
5 e.
6 f.
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FOOD WEBS
You have just learned that food chains show food relationships. However, in nature, many food
chains combine and overlap. They form a food web. A food web is a more complete way of
showing food relationships. A food web shows how a number of food chains are related.
Look at Figure C. Then answer the following
questions. (5 marks)
1. This diagram is called a
.
2. What does the diagram show?
.
3. What two organisms does a rabbit eat?
4. What organisms do wolves eat?
5. Which organism is the producer?
Figure C
6. Show one of the food chains represented in Figure C (draw it or write it). (3 marks)
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COMPLETE THE CHART
Classify each description as a habitat or a niche by putting a mark in the correct column.
(5 marks)
HABITAT OR NICHE
ITEM DESCRIPTION HABITAT NICHE
1 Eaten by fish.
2 Under rocks.
3 Hole in a tree.
4 Eat mice.
5 Nest on a tree branch.
6 Eat seeds and fruit.
7 Log
8 Jungle
9 Shared by organisms.
10 Not shared by organisms.
MATCHING
Match each term in Column A with its description in Column B. Put your answer in the Column
titled, Your Answer. You are to take the each letter beside an item in Column B and write it
beside the item in Column A that it is describing. (6 marks)
Your Answer Column A Column B
plants A organism that makes its own food
producer B animal that feed on other animals
decomposer C eats dead animals
consumers D organism that breaks down the wastes or remains of
other organisms
vultures E main producers on land
algae F main producers in lakes and oceans
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COMPLETE THE CHART
Classify each organism as a Producer, Consumer or Decomposer by putting a mark in the
correct column. (6 marks)
No. Organism Producer Consumer Decomposer
1 Seaweed
2 Hawk
3 Duck
4 Ants
5 Bacteria
6 People
7 Rabbits
8 Grass
9 Apple Tree
10 Dees
11 Earthworm
12 Beetle
FILL IN THE BLANK
Complete each statement using a term or terms from the list below. Write your answers in the
spaces provided. Some words may be used more than once. (5 marks)
niche webs food
sun soil
1. A producer can make its own .
2. The is the source of energy for an ecosystem.
3. Food chains combine to form food .
4. The role of an organism is called its .
5. A decomposer returns materials from dead organisms back to the .
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CROSSWORD PUZZLE (13 MARKS)
1
2
3
4
5
6
7 8 9
10
11
12
13
ACROSS DOWN
3 organism that gets food by eating other
organisms 1 an organism’s role in its environment
5 combining and overlapping of many
food chains 2 organism that makes its own food
6 model of the flow of energy through an
ecosystem 4 not dead
7 organism that feeds on dead organisms
8 all the living & non-living parts of an
environment
11 all members of one species that live in
the same area 9
study of the relationship between living things
and their environment
12 place where an organism lives
10 thin zone of the earth that supports all live
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Lesson 7: Studying Biomes
What are biomes?
The biosphere is divided into major areas called biomes. A biome is determined mainly by its
climate-like temperature and rainfall. Each biome has a different climate. Climate, in turn,
affects the soil. The earth's land areas are divided into six major biomes.
TUNDRA
Most of the year, the tundra is bitterly cold and covered with snow and ice. The ground remains
permanently frozen. It is called permafrost. Only certain small plants such as mosses and grasses
can grow in the tundra. Some animals, like reindeer and foxes, move in during the growing
season. But they move out again as the frigid weather approaches. Very few animals live year
around in the tundra.
CONIFEROUS FOREST
Conifers are cone-bearing trees such as pines and fir trees. Conifers make up the coniferous
forest biome. It is an area with a cold climate. Conifers form dense forests. The tree tops block
out much of the sunlight. Grasses and smaller trees cannot grow. Only some shrubs, ferns, and
mosses thrive. Coniferous forests are "home" for many animals, such as squirrels, moose, birds,
and insects.
DECIDUOUS FOREST
Deciduous trees such as maples and oaks shed their leaves in the fall. Deciduous forests thrive in
moderate climates. Summers may be hot and winters may be cold. But temperatures do not get
too hot or too cold for very long time. Deciduous forests receive a good supply of water. They
form dense forests. A deciduous forest provides habitats for many kinds of animals.
TROPICAL RAIN FOREST
A tropical rain forest is very warm and very moist all the time. It receives plenty of sunlight and
rain. This environment is excellent for plant growth and soil development. Plants grow thick and
tall. Tropical rain forests are found in areas near the equator. Rain forests support more plant life
and animal species than any other biome.
GRASSLANDS
The chief plant life in the grassland is grass. Grassland and deciduous forest temperatures are
about the same. But grasslands do not receive as much rainfall. Grasslands get enough rain to
support grasses-but not trees. Grasslands are excellent for grazing animals. The soil of grass
areas is very rich. Wheat and corn are grown here. Grasslands also are "home" for many small,
burrowing animals.
DESERT
A desert biome is very dry. It receives very little rainfall. Deserts are very hot during the day, but
they are cold at night. Desert soil is very dry and poor. Because of this, only a few kinds of
plants grow in the desert. And, very few animals can survive in the desert.
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Land Biomes
The map below shows the major land biomes of the earth.
1. In which biome do you live? (1 mark)
COMPARING BIOMES
The chart below shows the climates of the major land biomes.
2. What is the average yearly temperature range of the tropical rain forest?
(1 mark)
3. What biome gets between 75 and 125 cm of rainfall per year?
(1 mark)
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WHAT DO THE PICTURES SHOW?
The photographs show the six major land biomes. Write the correct name under each.
(6 marks)
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MULTIPLE CHOICE
In the space provided, write the letter of the word that best complete each statement.
(5 marks)
1. Permafrost occurs in
a) deserts. b) the tundra.
c) coniferous forests. d) tropical rain forests.
2. Trees such as pines and firs make up
a) tropical rain forests. b) the tundra.
c) coniferous forests. d) grasslands.
3. The biome that supports more plant and animal species than any other is the
a) tropical rain forest. b) deciduous forest.
c) coniferous forest. d) grasslands.
4. Very few animals can survive in
a) tropical rain forests. b) deserts.
c) grasslands. d) deciduous forests.
5. Trees that shed their leaves in the fall make up
a) the tundra. b) coniferous forests.
c) grasslands. d) deciduous forests.
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COMPLETE THE CHART
Classify each description by putting a mark in the correct column. (13 marks)
LAND BIOMES
No. Characteristics Tundra Coniferous
Forest Desert
Deciduous
Forest Grassland
Tropical
Rainforest
1
Very hot days
and very cool
nights
2
Trees with
needle shaped
leaves grown
here
3 Used as
farmland
4 Hot and wet all
year
5 Permafrost
6 Maple and oak
trees grow here
7 Cacti grown
here
8
Spruce and
moose are
common
9 Wheat and corn
grow here
10 Jungles
11 Tree lose leaves
in fall
12 Conifers grow
here
13 Reindeer live
here
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Pollution: How do people upset the balance of nature?
An environment is constantly changing. Sometimes, the changes work together to keep the
environment in balance. In a balanced environment, the size of the population remains about the
same over time.
Sometimes the balance in an environment is upset. Many times people upset the balance of
nature. People upset the balance of nature by destroying the habitats of other living things. For
example, people cut down forests for farms and towns. They build dams and dig mines. All of
these human activities can be harmful to other organisms in the environment. Many species of
animals are finding it hard to survive because of the ways people have upset the balance of
nature.
People also upset the balance of nature by causing pollution. You probably know that pollution
is a major problem. Pollution is anything that harms the environment. It occurs when harmful
substances or pollutants are released into the environment. Pollution of the air, land, and water
are all major problems. Today many different substances are poisoning the environment and
upsetting nature's balance. And we cannot think of just air pollution, or just water pollution, or
just land pollution. Pollution may start out in one part of our environment. But it does not remain
there. It S-P-R-E-A-D-S to all parts.
Pollution is increasing daily. Like other organisms, people also suffer from the effects of
pollution in the form of illness, birth defects, respiratory diseases, and many other problems.
Therefore, we must all work together to help reduce pollution.
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Studying Pollution
AIR POLLUTION
Study the pictures below and read the text describing each picture. Answer the questions.
The burning of fossil fuels is the major cause of air
pollution. Oil, coal and natural gas are fossil fuels.
When these fuels are burned, many harmful substances
are released into the air.
1. How do you think car-pooling helps reduce air
pollution? (1 mark)
When some harmful gasses are released into the air,
they combine with water to form acids. The acids fall
to the earth as acid rain. Acid rain kills living things.
It also damages building and statues.
2. What is acid rain? (1 mark)
Fuels need oxygen when they burn. They give off
carbon dioxide, which traps heat energy from the sun.
3. Scientists think that the increase of carbon dioxide
in the air is causing the temperature of the earth to
(rise, fall) (1 mark).
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List 3 laws you would create to help cut down on water pollution? (3 marks)
WATER POLLUTION
Water pollution occurs when harmful substances enter the water. Major sources of water
pollution include sewage, chemical wastes from factories, and fertilizers and pesticides washed
off from fields.
You have probably seen cans, bottles, and papers littering the ground. This is a form of land
pollution. Garbage and chemical wastes are other sources of land pollution. We produce
billions of tons of garbage each year. Chemical wastes are often buried in the ground.
What other ways can you conserve water? (3 marks)
COMPLETE THE CHART
Ten pollutants and sources of pollutants are listed below. Classify each by putting a mark in
the correct column. (5 marks)
POLLUTION
No. Description Land Water
1 Raw sewage discharge
2 Dumping chemicals into rivers
3 Pesticides
4 Detergents
5 Garbage
6 Burial of drums of toxic waste
7 Fertilizers
8 Use of DDT to control mosquitoes
9 Litter
10 Abandoning junk cars
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Explain how a pollutant gas in the atmosphere can become:
(a) water pollution (2 marks)
(b) land pollution (2 marks)
FILL IN THE BLANK
Complete each statement using a term or terms from the list below. Write your answers in the
spaces provided. Some words may be used more than once. (13 marks)
spreads illness air
pollution balanced reduce
sun does not defects
sewage survive wastes
pollutants
1. Anything that harms the environment is .
2. Pollution occurs when enter the environment.
3. The size of a population remains about the same in a
environment.
4. Many species are finding it hard to because of human
activity.
5. Major sources of water pollution include and chemical
.
6. Pollution can cause and birth in
people.
7. Pollution stay in one place. It to all parts of
the environment.
8. To help nature maintain a proper balance, we must pollution.
9. The burning of fossil fuels is the major cause of pollution.
10. Carbon dioxide traps energy from the .
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About 66,000 square miles of the world’s tropical rain forests are being destroyed each year.
How does this upset the balance of nature? (3 marks)
What is conservation?
Think about your pantry. It contains many kinds of foods. When they run low, you replace them.
But what if you knew that you could not replace certain items? What would you do?
You would try to make them last as long as possible. You would use them sparingly, or conserve
them. Conserve means to protect from being used up.
Earth is like a huge pantry. It has all the things we need to stay alive. It is also stocked with
things that modern people use, like ores for metals and fuels for energy. All of the things we get
from the environment are called natural resources.
There are two main groups of natural resources, renewable resources and nonrenewable
resources.
RENEWABLE RESOURCES are replaced by nature. Oxygen, water, soil, and living things are
renewable resources. Oxygen is made by plants during photosynthesis. Soil is made when rocks
break up. Water is renewed through the water cycle. Living things reproduce themselves.
NONRENEWABLE RESOURCES are not replaced by nature, at least, not in a reasonable
period of time. Fossil fuels, such as oil, coal and natural gas are nonrenewable resources and so
are minerals. We get metals from mineral ores. How would your life be different without fossil
fuels and metals?
At one time our supply of natural resources seemed endless. Now, we know differently. The
population of the world is increasing. We are using more, wasting more, and polluting more
natural resources than we did in the past.
Earth's "pantry" is limited. We must use our resources wisely. If we do not, there will not be
enough resources left for future generations.
Types of Conservation
The wise use of our natural resources is called conservation. Conservation of all natural
resources, including renewable resources is important. Even though renewable resources are
replaced, their supply is limited. People must be careful not to use them up faster than they can
be replaced.
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AIR CONSERVATION
Air pollution is very bad in most industrial areas and cities. But, air
pollution spreads everywhere. It reaches every place on Earth.
Polluted air can smell bad. It can cause health problems, like respiratory
diseases, lung cancer, and allergies. Polluted air also kills trees and reduces
food crops.
Motor vehicles and factories are the major causes of air pollution. Strict
laws concerning air pollution must be passed and enforced.
One of the least expensive ways to control air pollution is to walk instead
of drive and use public transportation.
WATER CONSERVATION
The average person drinks about 228 gallons of water each year. But water
is not only used for drinking. We use it in many other ways. For example we
use water for bathing, swimming, cleaning, cooking, gardening, and boating.
Water is also vital for proper sewage disposal, industry, agriculture, and
aquaculture.
Our water supply must be kept fresh and safe to drink. We must stop
dumping wastes and raw sewage into our water supply. We can also
conserve water by turning off the water when brushing teeth and taking
showers instead of baths.
SOIL CONSERVATION
It takes nature from 500 to 1000 years to produce about two and one-
half centimeters (one inch) of topsoil.
Soil can be carried away by the wind and moving water. This removal
of soil is called erosion. Erosion can be reduced. To prevent too
much soil erosion, people must practice soil conservation.
Some ways to conserve soil are:
a) Cover the soil with plants, such as grass or shrubs. The roots of
plants help hold soil together.
b) Restrict the cutting down of forest. Trees act as windbreaks and
help prevent soil from being blown away by the wind.
c) Plant crops across the slope of a hill instead of up and down the hill. This helps prevent soil
from being washed away by water running down the hill.
d) Add materials like humus or natural fertilizers to the soil.
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WILDLIFE CONSERVATION
All natural plants and animals living in an area are
called wildlife. Wildlife is part of nature. They
provide us with food, clothes and many other
products. Wildlife is also pretty to look at.
Human activity can cause many forms of wildlife to
become extinct (die out). We pollute and overhunt.
We destroy wildlife habitats with construction and
mining. These actions disturb nature’s balance.
Some methods for wildlife conservation are:
(a) Protecting habitats of organisms
(b) Enforcing strict hunting and fishing laws.
(c) Setting aside refuges, parks, and other public lands for
wildlife.
(d) Provide special ―breeding grounds‖ for endangered
species (organisms in danger of becoming extinct.
Forests are ―home‖ for many plants and animals. Forests
provide us with oxygen, lumber, wood pulp, medicines and
many other products. Wood pulp is used to make paper,
including the pages of this book.
Tropical rain forests have more plant and animal species
than any other place on earth. Many of the wildlife habitats
are being lost in these forests.
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Fires caused by human carelessness destroy many forests. Public education about dangers of
forest fires is one way to help conserve forests.
Other methods of forest conservation include:
a) Planting new trees to replace those that have been
chopped down for lumber or other products.
b) Chopping down only certain parts of a forest to allow
seeds from remaining trees to provide replacements.
c) Removing only older or unhealthy trees from forest
regions.
METAL CONSERVATION
To recycle means to "use over again." Some resources, like
metals, can be recycled. Aluminum cans, glass bottles,
newspapers and some of the metals used to make cars can all be
recycled. They can be melted down and reused. Most can be
recycled over and over again. Recycling is an important way to
conserve minerals.
FUEL CONSERVATION
Fuels are nonrenewable resources. Once a fuel is used, it is gone. It cannot be recycled. The best
way to conserve a fuel is not to waste it. Use it sparingly. Use it as you would a non-replaceable
item in your pantry.
Here are some ways people can help conserve fuel:
a) Use cars that get good gas mileage. Drive the speed limit.
b) Walk, bicycle, or car pool when possible.
c) Turn off lights when you leave a room to save the fuel used to produce electricity.
d) Use electrical appliances that are energy saving.
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Assignment #2: AIR CONSERVATION
What laws would you suggest to help cut down on air pollution? (3 marks)
WATER CONSERVATION
What other ways can you conserve water? (3 marks)
MATCHING
Match each term in Column A with its description in Column B. Put your answer in the Column
titled, Your Answer. You are to take the each letter beside an item in Column B and write it
beside the item in Column A that it is describing. (5 marks)
Your
Answer Column A Column B
water, air, soil and living things A wise use of resources
minerals and fossil fuels B cause of most pollution
conservation C non-renewable resource
pollution D renewable resource
people E harm all living things
Make a list of five things you use often. Identify the natural resource (or resources) that each of
the five things came from. (10 marks)
NO. WHAT I USE OFTEN NATURAL RESOURCE
1
2
3
4
5
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FUEL CONSERVATION - MULTIPLE CHOICE
In the space provided, write the letter of the word that best completes each statement.
(8 marks)
1. All the things nature gives are called
a) pantries b) ores
c) natural resources d) renewable resources
2. The things that nature replaces in a short period of time are called
a) renewable resources b) non-renewable resources
c) fossil fuels d) wildlife
3. An example of a renewable resource is
a) coal b) aluminum ore
c) oxygen d) oil
4. Things that nature does not replace in a reasonable period of time are called
a) renewable resources b) non-renewable resources
c) pollution d) natural resources
5. An example of a non renewable resource is
a) water b) soil
c) air d) minerals
6. The wise use of our natural resources is called
a) recycling b) consideration
c) conservation d) erosion
7. Organisms in danger of dying off are considered
a) endangered b) extinct
c) conserved d) wildlife
8. The use of resources over and over again is called
a) erosion b) cycling
c) recycling d) replacement
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Lesson #8: Our Universe
Why do we study space?
Have you ever looked deep into an evening sky? Did you wonder how far away the stars are and
what lies beyond the stars? People have always wondered about the heavens. Why?
The answer lies in the natural curiosity of the human mind. We see the sky above us and ask
questions. We try to figure out the answers to these questions. However, more often than not, the
answers lead to more questions. The study of heavenly bodies is called astronomy. Scientists
who study astronomy are called astronomers.
When we study astronomy, we learn a little bit more about the universe. The sun, moon and
planets are part of the universe. So are the stars. Everything that exists is part of the universe. So
the universe is everything that exists.
Earth is part of the universe. So when we learn more about the universe, we learn more about the
earth's place in the universe. For example, the more we learn about the other planets in the solar
system, the more we know about planets in general. As we learn more about planets in general,
the better we understand the planet earth.
For many centuries, people thought that the earth was the centre of the universe. They thought
that the sun and the stars revolved around the earth. The problem with this explanation was that
the planets did not seem to revolve around the earth in any simple way. People made very
complex models to try to explain how the planets moved around the earth.
Nicholas Copernicus was a Polish astronomer who lived in the 1500s. He studied the sky and
made very careful observations even though he had no instruments to help him. Copernicus's
studies convinced him that the earth and other planets revolved around the sun. For many years,
most people did not believe his ideas. Today we know that they are true. Copernicus's ideas
changed the way humans viewed the universe. We now know that the earth is not the centre of
the universe but just one small planet among countless stars.
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SPACE EXPLORATION
Scientists do more than study space. They also send things and people into space. In 1957, the
Soviet Union launched the first artificial satellite, called Sputnik, into orbit. Since that time, the
United States, Soviet Union and several other countries have launched things into orbit around
the earth. There are a number of reasons to put people and satellites into orbit.
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Assignment #3: Why Do We Study Space?
STUDYING SPACE - TRUE AND FALSE
Circle ―true‖ if the sentence is true, or ―false‖ is the sentence is false. (10 marks)
1. Earth is a part of the universe. True False
2. The sun revolves around the earth. True False
3. The moon revolves around the earth. True False
4. The earth revolves around the sun. True False
5. Copernicus was an astronaut. True False
6. The study of heavenly bodies is called
astronomy.
True False
7. The earth used to be the centre of the
universe.
True False
8. People once thought that the earth was
the centre of the universe.
True False
9. Astronomers study astronomy. True False
10. Today, we know everything there is to
know about space.
True False
MATCHING
Match each term in Column A with its description in Column B. Put your answer in the Column
titled, Your Answer. You are to take the each letter beside an item in Column B and write it
beside the item in Column A that it is describing. (5 marks)
Your Answer Column A Column B
astronomy A revolves around the earth
earth B planets revolve around it
sun C everything that exists
moon D the study of objects in space
universe E revolves around the sun
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FILL IN THE BLANK
Complete each statement using terms from the list below. Write your answers in the spaces
provided. Some words may be used more than once. (11 marks)
earth astronomers 1957
sun Soviet Union the 1500s
Polish satellite
1. The revolves around the .
2. The moon revolves around the .study objects in space.
3. Copernicus lived in .
4. Sputnik was launched in .
5. Sputnik was a .
6. Copernicus was a astronomer.
7. Sputnik was launched by the .
8. Planets revolved around the .
9. Satellites orbit the .
REACHING OUT
Some people believe that society should build places for people to live in space. Why might
people want society to do this? (3 marks)
What are satellites and space probes?
The moon is a satellite of the earth. A satellite is something that orbits another object in space.
On October 4, 1957, the Soviet Union launched Sputnik into orbit around the earth. Sputnik
became the earth's first artificial satellite.
Since Sputnik, hundreds of satellites have been launched. Satellites perform all sorts of
functions. There are four basic types of satellites.
EARTH SENSING SATELLITES: These satellites have cameras or some other kind of
sensors pointed down at the earth. As the satellite flies over different places, the sensors on the
satellite study these places. Satellites are very helpful in the study of isolated places that are hard
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for people to get to, such as the tops of mountains. Earth sensing satellites also are used by the
military of some countries to study what is going on in other countries.
SPACE SENSING SATELLITES: We need the earth's atmosphere to survive, but the
atmosphere often is in the way when we try to study things in space. Satellites are often put in
orbit above the earth's atmosphere. These satellites have a clear view of what scientists want to
study in space.
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COMMUNICATION SATELLITES: Radio waves cannot travel through the ground, and the
curvature of the earth gets in the way of radio signals that arc sent far across the planet. Instead,
radio signals are sent to satellites in space. The satellites, in turn, send the signal to another place
on the earth. In fact, sometimes a satellite sends a message on to another satellite, which then
sends it to the ground. Messages can be sent all the way around the world this way.
NAVIGATION SATELLITES: Ships, planes, and even cars can pinpoint their location on the
earth by "listening" to the signals sent by several navigation satellites.
In studying planets and other objects in the solar system, sometimes there is no substitute for
"being there." However, it would be very expensive, and very dangerous, to send people to other
planets. Instead, scientists send robots similar to satellites toward these objects. These robots are
called space probes.
Space probes come in all shapes and sizes and can perform various functions. Most space probes
have cameras of some type to take pictures of the objects they are studying. Because space
probes are much closer to the objects they are studying, they can take much better pictures than
we can from Earth. Voyager 1 and Voyager 2 are two space probes that flew by Jupiter, Saturn,
Uranus, and Neptune.
Some space probes are designed to land on other planets. These probes can then study the
surface of the plant. Viking 1 and Viking 2 were two probes that landed on Mars in 1976.
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Assignment #4: KINDS OF SATELLITES - SPACE PROBES
What are Satellites and Space Probes?
TRUE AND FALSE
Circle the word ―true‖ if the sentence is true, or ―false‖ is the sentence is false.
(10 marks)
1. Sputnik was the earth’s first satellite.
True False
2. Sputnik was the earth’s first artificial satellite.
True False
3. The earth has one natural satellite.
True False
4. The earth has no natural satellites
True False
5. Satellites can be used to study the earth.
True False
6. Satellites can be used to study the space.
True False
7. Space probes carry people to other planets.
True False
8. Space probes study objects in space.
True False
9. Space probes cannot land on planets.
True False
10. Voyager 1 and Voyager 2 studied Mars.
True False
MATCHING
Match each term in Column A with its description in Column B. Put your answer in the
Column titled, Your Answer. You are to take the each letter beside an item in Column B
and write it beside the item in Column A that it is describing. (5 marks)
Your
Answer Column A Column B
navigation satellites A used to study other objects in space from earth’s orbit.
earth sensing satellites B weather satellites
space sensing satellites C Voyager 1 and Voyager 2
communication satellites D relay telephone calls and television programs.
space probes E help ships, planes and cars find their way
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WORK SEARCH
The list on the left contains words that you have used in this Lesson. Find and circle each word
where it appears in the box. The spellings may go in any direction: up, down, left, right or
diagonally. (5 marks)
D C U T S P A C E E N E
E O I T R S S A B T F I
R M I R E G A Y O V T Y
T M H O E V T O B I E R
R U O C R J E P N K I T
E N I K W N L R E I S I
F I G E F O L F W N Y G
I C H T B Z I Q T G D O
N A V I G A T I O N Z L
E T A L S O E D N E L A
J I K E A R T H V O J K
I O M X N M A R E E T H
M N J U P T Q M L M S T
REACHING OUT
Why is it cheaper to send space probes to other planets instead of sending people?
(3 marks)
SATELLITE
NAVIGATION
ROCKET
VOYAGER
VIKING
COMMUNICATION
EARTH
NEWTON
SPACE
MARS
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What is a Space Shuttle?
TRUE AND FALSE
Circle the word ―true‖ if the sentence is true, or ―false‖ is the sentence is false.
(10 marks)
1. The Shuttle has two solid rocket boosters. True False
2. The external tank is carried into space. True False
3. The external tank is not reusable. True False
4. The Shuttle only carries people into space. True False
5. The Shuttle has a large cargo bay to carry things into space. True False
6. The Shuttle lands on water. True False
7. The Shuttle lands like an airplane. True False
8. The Shuttle takes off like an airplane. True False
9. The Shuttle takes off like a rocket. True False
10. The Shuttle can bring satellites back to Earth. True False
FILL IN THE BLANK
Complete each statement using a term or terms from the list below. Write your answers in the
spaces provided. Some words may be used more than once. (13 marks)
launch external tank solid rock booster repair
orbits shuttle orbiter joined glides
Space Shuttle wheels is not
1. The is the first reusable aircraft.
2. The main parts of a Shuttle system are the , two
and an .
3. Extra upward thrust is supplied by the .
4. At lift-off, all the parts of the Shuttle system are .
5. The first parts of the Shuttle system to separate are the ____________________________-.
6. The external tank reused.
7. The Shuttle Earth.
8. Not only can the Shuttle be used to satellites, it can be
used to them.
9. When its mission is completed, the Shuttle back to earth.
10. The Shuttle lands on like a regular airplane.
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REACHING OUT
When was the last shuttle launch – why did the space shuttle program form to an end – or did it?
(3 marks)
WHAT IS A SPACE SHUTTLE?
Imagine that your family owned a car that could be used JUST ONCE. After only one trip - long
or short, it had to be junked. Sounds ridiculous? It certainly does! But this is precisely how the
space program operated until April 12, 1981. On that date, Columbia, America's first Space
Shuttle was launched. It went into orbit - and then returned to earth.
A Space Shuttle is a reusable space vehicle. Until the Shuttle, no part of a space launch (that
blasted off) was reused. Some parts fell into the ocean. Others burned up while returning to
Earth. Even the capsules that carried astronauts were not reused
This approach to space exploration was too expensive. Scientists knew this. They wanted a
cheaper way to send things into space, so they developed the Space Shuttle.
The Space Shuttle is designed to be used over and over again. Only one part--its main fuel tank--
must be replaced. A Space Shuttle system has three main parts:
the Shuttle orbiter itself, with its three main engines
two solid rocket boosters (for extra thrust)
external tank (a large fuel tank)
1. At blastoff, all parts are connected. The main engines and the boosters both burn with a
deafening roar. The Shuttle lifts off and heads towards space.
2. After a few minutes, the boosters have used up their fuel. They separate and parachute back
to earth. They are recovered and re-used. The main fuel tank is still attached and continues
to feed the main engines.
3. When the Shuttle reaches its proper speed and position, the main fuel tank breaks away. It
burns up as it plunges back through the atmosphere. This is the only part that is not reused.
4. The Shuttle is now in orbit around the Earth. It may continue in orbit for several days. While
in orbit, the crew carries out their mission.
5. Its mission completed, the Shuttle returns to earth. Since it has no fuel, it glides back to
earth.
6. The Shuttle lands on wheels, like an airplane. It is then made ready to be reused.
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LIFTOFF TO LANDING
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USES OF THE SPACE SHUTTLE
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Surviving in Space
Select the correct word to fill in the blank from the words in brackets.
Outside the spacecraft, the temperature is extremely cold. The temperature inside the spacecraft
(is, is not) extremely cold. Outside the spacecraft, there is no air pressure. People
(can, cannot) live where there is no air pressure. The air inside the spacecraft is
(cold, pressurized). The pressure inside the cabin is like the air pressure
(on Earth, in space). The spacecraft carries tanks of oxygen. We
(can, cannot) live without oxygen. (5 marks)
FILL IN THE BLANK
Complete each statement using a term or terms from the list below. Write your answers in the
spaces provided. Some words may be used more than once. (6 marks)
temperature airplanes oxygen
spacecraft earth under water
1. A must supply everything an astronaut needs.
2. The in a spacecraft is kept at a comfortable level.
3. The pressure in a spacecraft is like the pressure on the .
4. Living things need to survive.
5. Astronauts train for weightlessness on and
.
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Answer the following questions: (6 marks)
1. Is there pressure outside the spacesuit? (yes, no)
2. Is there pressure inside the spacesuit? (yes, no)
3. Do the astronauts feel the pull of gravity in a moving spacecraft? (yes, no)
4. How much do the astronauts seem to weigh in space?
5. How do astronauts prepare for the feeling of weightlessness?
6. How is being in water like being in space?
MATCHING
Match each term in Column A with its description in Column B. Put your answer in the Column
titled, Your Answer. You are to take the each letter beside an item in Column B and write it
beside the item in Column A that it is describing. (5 marks)
Your
Answer Column A Column B
carbon dioxide A copies zero gravity
shields B needed for life
airplane C carries everything an astronaut needs
spacesuit D block radiation
oxygen E waste gas
REACHING OUT
Spacesuits are white for good reason. What is the reason? (1 mark)
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How do humans survive in space?
Everything that surrounds an organism is called its environment. Air and water are parts of the
environment. So are the temperature, air pressure, and food.
Our environment is well suited for life. We have air to breathe, food to eat, and water to drink.
The air pressure is just right. In most places the temperature is never too hot or too cold. The
atmosphere blocks out harmful radiation. In short, we live in a "friendly" environment.
The environment in space, however, is not friendly to humans. It presents many problems. You
could not live in space the same way that you live on earth. There is no air to breathe. There is
also no air pressure. The temperature is either much too hot or much too cold. No food grows in
space. And there is nothing to block out harmful radiation.
There are other problems too. Living things produce wastes. The wastes must be eliminated. On
earth, we have no problem eliminating our wastes. Every time we breathe out we release carbon
dioxide into the air. Heat and moisture from our skin goes into the air, too. We use water to flush
away the liquid and solid wastes we produce.
In space, getting rid of wastes is not so easy. In fact, just keeping clean is a problem.
On earth, gravity holds you to the ground. In a moving spacecraft, there is no gravity. Actually,
gravity from outer space does pull upon the spacecraft. But the movement of the spacecraft
cancels it out. The result is "zero" gravity. In zero gravity a person seems to weigh nothing. Just
imagine. You would float around the spacecraft if you didn't hold onto something!
Because of all these problems of living in space, astronauts must bring along their own
environment! It must be like the environment found on earth. Special clothing and instruments
have been designed so that the traveler in space has everything that is needed to stay alive.
EATING IN SPACE:
Everything in space is weightless. It is not possible to eat
a regular meal like you do on earth. The food would float
around inside the cabin. An astronaut would have to
chase after the meal.
Early astronauts ate soft foods from tubes that looked like
toothpaste tubes. The astronauts would squeeze the food
right into their mouths.
The Space Shuttle has a galley where the crew can
prepare meals. This galley even has an oven to heat up
pre-made foods. Some food is dehydrated, so the shuttle
crew must add water to it.
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OUTSIDE THE SPACECRAFT
An astronaut may not spend all the time in the spacecraft. Some of
the time may be spent taking ―space walks‖ in a pressurized suit.
The space suit has air, food and water for the astronaut.
A ‖rocket‖ backpack allows astronauts to fly in space all by
themselves.
WEIGHTLESSNESS IN SPACE
Very little can be done about weightlessness. Astronauts prepare themselves for this funny
feeling. Airplanes can be piloted to mimic zero gravity. Astronauts also practice missions
underwater. In this way, an astronaut learns what to expect.
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Lesson #9: What is the solar system?
Everywhere you look today, you see the word "solar". Solar energy. Solar power. What exactly
does the word" solar" mean? "Solar" means "of or relating to the sun".
The solar system, then, is the system of the SUN. This system is made up of the sun and all the
objects that travel around the sun. These satellites of the sun travel in "paths" called orbits. They
are held in their orbits by the sun's gravity.
PLANETS: Except for the sun itself, planets are the largest objects in the solar system. Nine
planets orbit the sun. One of them is our own home, planet Earth.
MOONS: Most planets have moons. Moons orbit the planets.
ASTEROIDS: These are large chunks of rock. Most asteroids are found in a "belt" between the
planets Mars and Jupiter.
COMETS: These are made up of rocks, dust and ice. A comet has a small "head" but a very long
"tail". The tail extends millions of miles into space and it points away from the sun. Comets
travel around the sun in long elliptical orbits. The most famous comet is Halley's Comet. It takes
Halley's Comet 76 years to complete one trip around the sun.
METEROIDS: These are small bits of rock. Most are as small as a grain of sand. Some,
however, are as large as boulders. Billions and billions of meteoroids are scattered throughout
the solar system.
When a meteoroid enters the earth's atmosphere, friction causes the meteor to glow brightly. It
seems to "burn up" as the rock changes it to a gas. While it is "burning up" it is called a meteor
or a shooting star. We see it as a bright trail or streak of light in the night sky.
Most meteors burn up completely in the atmosphere. A few reach the earth's surface. A meteor
that has reached the earth's surface is called a meteorite.
What are the Inner Planets?
The four planets closest to the sun are called the inner planets. The inner planets are similar in a
number of ways. The inner planets are also called the terrestrial planets. Terrestrial means "like
the Earth. "
The terrestrial plants are relatively small compared to the other planets in the solar system.
Unlike the outer planets, they have very little hydrogen and helium. Instead, they are made
mostly of rock and iron.
Everything in the solar system formed out of the same mixture of interstellar matter. This
interstellar matter was mostly hydrogen and helium. What happened to the hydrogen and helium
on the inner planets?
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Scientists believe it simply blew away. The inner planets are much smaller than the outer planets.
Therefore, the pull of gravity on the inner planets is much smaller. Hydrogen and helium are
very light. It takes a strong pull to keep them around a planet. The inner planets did not have a
strong enough pull.
Instead, the hydrogen and helium floated out into space. There, particles being shot off from the
sun pushed the hydrogen and helium out of the solar system.
MERCURY
Mercury is the planet closest to the sun. It is about
one third the size of earth and is only one twentieth
as massive. Mercury has no moons and is very
similar to Earth’s moon. Like the Moon, Mercury
has virtually no atmosphere and is heavily cratered.
Mercury rotates on its axis once every 59 days. Since
it is closer to the sun than any of the other planets,
Mercury takes less time to go around the sun than
any other planet. It only takes Mercury 88 days to go
all the way around the sun.
The rate of rotation and revolution on Mercury act together to give every place on Mercury 88
days of daylight followed by 88 days of darkness. This causes huge differences in daytime and
nighttime temperatures on Mercury. The temperature on Mercury during the day is about 400
degrees Celsius (750°F). At night, the temperature is about 180 degrees below zero Celsius (-
290°F). That's quite a change!
The Mariner 10 spacecraft flew past Mercury three times in 1974 and 1975. This is the only
spacecraft to ever visit Mercury. Figure A shows a picture of the planet which was made by
putting many detailed photos together.
VENUS
Venus has nearly the same size and mass as Earth. It
is often referred to as Earth's sister world. Venus
takes 225 days to go around the sun. Venus rotates
very slowly and in the opposite direction of most of
the other planets. Scientists believe that Venus once
rotated at the same rate that it revolved around the
sun, once every 225 days. It always had the same
side towards the sun. Earth, however, pulls on
Venus as well and Venus now spins so that when if
is closest to Earth, it always has the same side facing Earth.
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Venus is closer to the sun. If you guessed that Venus is warmer than the earth, you would be
right. But the fact that Venus is closer to the sun is only part of the reason that it is so warm. The
atmosphere of Venus has a lot of carbon dioxide in it. Carbon dioxide acts like a one-way door.
The carbon dioxide lets the warmth of the sun reach the surface of Venus very easily. It does not,
however, let that heat escape into space very easily. Instead, Venus has gotten warmer and
warmer, like you do under a blanket. The temperature on Venus is about 480 degrees Celsius
(900°F).
Furthermore, Venus's atmosphere is so thick that the spacecraft that have orbited it have not been
able to photograph the surface. Instead, radar is used to map the surface. Magellan1 is a radar
mapping space probe that is currently mapping the surface.
EARTH
Earth is your home: the home of your family, the
home of your friends, the home of everyone you
know. Only a few people (astronauts and
cosmonauts) have ever left Earth.
We do not usually think of Earth as a planet. It's
kind of like not seeing a forest because of the trees.
We are so close to Earth (it's right beneath our
feet) that we do not recognize it as a planet. It is a
planet, and as our home world, it is very important
to us.
Earth is the only planet in the solar system we know that has living things on it. There are several
reasons why this is so. The temperatures on Earth are just right for living things to have formed
several million years ago, and for living things to survive today. The temperature on Earth is
important for another reason. Water is a liquid on Earth. On planets closer to the sun, the
temperatures are higher than Earth's and water is found only as a gas. On planets farther away
from the sun than Earth, it is colder and water is found only as a solid.
On Earth, however, we have oceans of liquid water, and liquid water is needed by living things.
The next time you go outside, consider how lucky you are to have Earth for your home.
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MARS
Mars is about half the size of Earth and is twice the size of the moon. A red dust covers the
planet and you can recognize Mars in the sky because of its reddish colour.
People have often wondered about Mars. In 1877, an Italian astronomer named Giovanni
Schiaparelli noticed dark markings he called canali, which means" channels." The American
astronomer Percival Lowell interpreted Shiaparelli's writings to mean that Mars had canals like
the canals on Earth. Lowell thought that these canals must have been created by Martians,
intelligent beings on Mars. For half a century, people would imagine little green men and women
lived on Mars. In fact, when a fictional story about an invasion from Mars was broadcast on the
radio in the 1930s, many people thought it was real!
We now know that there are no little green men and women on Mars, but the possibility that
there could be life still exists. Water is a necessary ingredient in the development of life on a
planet, and Mars once had a great deal of water. Even though the planet is now very dry, if there
had been life on Mars when the planet had more water, the life forms could have evolved to live
in the present dry climate.
In 1976, two Viking spacecraft landed on Mars. One of their main objectives was to check the
Martian surface for life. They found many of the necessary ingredients for life but no evidence
that there was actually anything alive on the planet.
What are the Outer Planets?
Beyond the orbit of Mars lies an asteroid belt that mark the boundary between the inner planets
and the outer planets. The inner planets are generally the same size and made of the same rocky
material.
In general, the outer planets are totally different from the inner planets.
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Jupiter, Saturn, Uranus, and Neptune are gas giants. The smallest of the four, Neptune, is 60
times the size of Earth. As their name suggests, gas giants are primarily made of gases. They are
very similar to stars that never started shining. In fact, some scientists suggest that if Jupiter had
been a few times larger, it would have become a star.
The one outer planet that is not a gas giant is Pluto, the small planet that belongs in a class by
itself.
JUPITER
Jupiter, like the other planets, is named
after a mythological Roman god. The
mythological Jupiter was king of the gods
and Jupiter is king of the planets. Jupiter
is the largest planet in the solar system.
The most prominent feature of Jupiter is
its red spot. This storm in its atmosphere
has been raging for as long as we have
been able to see it. With the exception of
the red spot, Jupiter's atmosphere can be
described as a number of bands stretching around the planet.
Jupiter has four very large moons that can be seen with even the weakest telescopes. These
moons, discovered by Galileo, are called the Galilean satellites. The giant planet also has about a
dozen smaller moons. Io, the smallest moon, is a fiery world with very active volcanoes, caused
by Jupiter's gravitational pull on the moon. Europa is an extremely smooth moon that has an icy
surface. Caliosto and Ganymede are two moons about the size of Mercury. Calisto is very similar
to Mercury and Earth's moon in that it is covered with craters. Ganymede is not completely
understood since it is largely made of ice. From a geological perspective, ice is a very complex
material.
Almost all we know about Jupiter was learned by the Voyager 1 and Voyager 2. These two
spacecraft took a tour of the outer solar system in the 1970s and 1980s and Jupiter was the first
planet they encountered. The cameras on the Voyager spacecraft took pictures far, far better than
any that could be taken from Earth. The spacecraft also carried other equipment that performed a
number of other experiments as the spacecraft flew past Jupiter.
One of the most important discoveries made by Voyager spacecraft was that Jupiter has a ring
around it. This ring is much fainter than the one around Saturn or Neptune. The discovery of a
ring around Jupiter showed that most gas giants in the solar system have rings.
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SATURN
Saturn is known as the ringed planet.
From Earth, it is relatively easy to see
four distinct rings through a telescope.
When Voyager reached Saturn, however,
no one was prepared for what it found.
There were thousands of rings! Almost
too many to count. The rings are made of
dust and rocks of various sizes.
Voyager 1 flew past Jupiter in March,
1979. The gravity of Jupiter then catapulted it towards Saturn, which it reached in November
1980. This push allowed Voyager 1 to reach Saturn much more quickly using far less energy.
Voyager 2 was pushed by Jupiter in the same manner. What's more, Saturn's gravitational pull
pushed Voyager 2 on to Uranus. Uranus in turn, pushed Voyager 2 on towards Neptune.
Scientists were able to plot this course for the Voyager spacecraft because the planets were on a
special alignment. This alignment only happens about once every two hundred years.
Saturn has a large number of moons. Titan, the largest of these moons is bigger than the planet
Mercury. Titan is both larger and colder than Earth's moon. Titan's temperature and mass allow it
to have a thick atmosphere. In fact, it has more of an atmosphere than Mars or Earth. Like Earth,
Titan's atmosphere is mostly made up of nitrogen. The conditions on Titan are very similar to
what existed on Earth a long time ago, with one important exception. Titan is much colder than
Earth. The temperature on Titan is 177 degrees below zero Celsius (-180°F). Still, studying Titan
may help us understand the Earth's own history.
URANUS
For many years, Uranus and Neptune have
been thought of as twins. Both planets are
roughly the same size, with a diameter of
about 50,000 kilometres. They both also
have a deep blue colour, like the sky on a
very clear day. However, as we have
learned more about these two worlds,
some differences have been discovered
between these two brothers.
Uranus was discovered in 1781. Five years
after the United States had declared
independence from Britain, an amateur astronomer named William Herschel was using a six-
inch telescope to study some stars. One of the stars appeared as a disk on his telescope rather
than a point of light. He watched it over a period of many nights and discovered it moved with
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respect to the other stars. What Hershel had discovered was not a star but was a planet, what we
now call the planet Uranus.
On March 10, 1977, Jim Elliot, a professional astronomer, studied Uranus as it passed in front of
a bright star. Astronomers can tell a lot about a planet by watching it eclipse a star. The light
from the star was blocked as the planet passed in front of the star. Furthermore, the light was
blocked out just before and just after it passed by the planet. The cause of this was a set of rings
that were too small to be seen from Earth. Until this discovery, Saturn was the only planet we
knew that had rings. Now we know that several planets have them.
When Voyager 2 visited Uranus, its cameras showed that the atmosphere of the planet is very
smooth, unlike the storms and bands visible in the other gas giants.
NEPTUNE
Once Uranus had been discovered, astronomers
rushed to plot and calculate its orbit around the
sun. They could not figure it out. Even after
calculating the effect of all the other planets on
Uranus, it still did not follow the predicted
orbit. Scientists suggested that there must be
another planet farther out than Uranus that had
not been discovered. They then set out to
calculate where it would be. A search was
made.
On September 23,1846 Neptune was discovered almost exactly where John Couch Adams and
Urbain Jean Joseph LeVerrier, two mathematicians, had predicted it would be found. This was a
tremendous triumph for science and mathematics.
While Neptune resembles Uranus in its colour, its atmosphere resembles Jupiter's atmosphere.
Instead of a large red spot, Neptune has a large dark spot.
After rings were discovered on Uranus and Jupiter, scientists wondered if Neptune had rings. A
search for rings around Neptune was undertaken. The same process that found the rings around
Uranus was used, but was not effective. Scientists would sometimes find the light blocks on one
but not the other. Since rings go around both sides of the planet, they should block the light on
both sides.
Voyager 2 solved the controversy by clearly showing that Neptune had rings. An individual ring
was sometimes thicker on one side than it was on the other. Scientists on Earth could only detect
the thicker part of the rings.
In 1610, Galileo first saw the rings around Saturn. For the next 367 years, people believed that
Saturn was the only planet that had a ring system. In thirteen years, from 1977 to 1990, scientists
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have learned that all the gas giants have rings. That is an amazing discovery in such a short
period of time.
PLUTO
After the discovery of Neptune astronomers
continually wondered whether there could be a
ninth planet. Sometimes, searches were made for
such an object. One search was carried out at
Lowell observatory, founded by the same
Percival Lowell who thought there were canals
on Mars. Clyde Tombaugh, an assistant at the
observatory, would study two pictures of the
same section of the sky taken at different times.
He would look to see whether any object in the picture had moved. On February 18,1930,
Tombaugh discovered Pluto.
We do not know very much about Pluto since it is so far away and no spacecraft have visited it.
Pluto is the smallest planet in the solar system and is slightly smaller than the Moon. It has a
moon of its own named Charon and a very thin atmosphere made mostly of methane.
Since it is so far from the sun, Pluto is very cold. It usually is about 225° below zero Celsius (-
373°F) on Pluto.
Some scientists do not think that Pluto should be considered a planet. It is very different than all
the other planets in the solar system. It is most like some of the moons of the gas giants.
Unfortunately, there are no plans to send a spacecraft to Pluto, even though it is the only planet
that has not yet been visited. For the time being, at least, much about Pluto will remain a
mystery.
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Assignment #5: What is the Solar System?
Using the above picture, fill in the chart listing the names of the other seven planets in the order
of their location to the sun—the first and last planet have been done for you.
ORDER OF THE PLANETS FROM THE SUN (7 marks)
1 Mercury (closest to sun)
2
3
4
5
6
7
8
9 Pluto (farthest from the sun)
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THE PLANETS AND THEIR MOONS (10 marks)
1 Which two planets DO NOT have any moons? 1.
2.
2 Which two planets have only ONE moon? 1.
2.
3 Which planet has two moons? 1.
4 Which two planets have the most moons? 1.
2.
5 Which four planets have rings?
1.
2.
3.
4.
6 The four planets closest to the sun are called the Inner
Planets. Name them.
1.
2.
3.
4.
7 The five planets farthest from the sun are called the
Outer Planets. Name them.
1.
2.
3.
4.
5.
FILL IN THE BLANK
Complete each statement using a term or terms from the list below. Write your answers in the
spaces provided. Some words may be used more than once. (12 marks)
moons comet planets
Jupiter solar system Pluto
satellite sun Uranus
asteroids Saturn
1. The sun and all the space bodies that orbit the sun make up the
.
2. The largest objects that orbit the sun are called .
3. The objects that orbit most planets are called .
4. The rocks that form a ―belt‖ between Mars and Jupiter are
5. A is made up of small bits of rock, dust and ice.
6. A comet orbits the .
7. The planet farthest from the sun is .
8. The planets with rings are ,
, and .
9. The largest planet is .
10. Any space object that orbits another space object is called a
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TRUE AND FALSE
Circle ―true‖ if the sentence is true, or ―false‖ is the sentence is false. (5 marks)
1. The stars are part of our solar system. True False
2. The planets are satellites of the sun. True False
3. The Asteroid Belt is located between Mars and Jupiter. True False
4. Saturn is the only planet with rings. True False
5. All planets have moons. True False
What are the Inner Planets?
FILL IN THE BLANK
Complete each statement using a term or terms from the list below. Write your answers in the
spaces provided. Some words may be used more than once. (12 marks)
Mercury Earth liquid
Venus Mars Viking spacecraft
terrestrial Mariner 10 moon
1. _____________________ is the planet closest to the sun.
2. Mercury is similar to Earth’s .
3. Mercury, Venus, Earth and Mars are planets.
4. ____________________ and are about the same size.
5. ________________ was a spacecraft that studied Mercury.
6. ________________has a very thick atmosphere.
7. _________________is the only planet known to have life on it.
8. On Earth, water is usually found in form.
9. ____________is a red planet.
10. In 1975, two landed on .
MATCHING
Match each term in Column A with its description in Column B. Put your answer in the Column
titled, Your Answer. You are to take the each letter beside an item in Column B and write it
beside the item in Column A that it is describing. (5 marks)
Your Answer Column A Column B
Magellan A half the size of Earth
Viking B studied Mars
Marnier 10 C studying Venus
Venus D studied Mercury
Mars E same size as Earth
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Use the clues to complete the crossword puzzle. (10 marks)
ACROSS DOWN
1 First planet known to have rings. 2 Found in a belt between Mars & Jupiter.
3 Body that orbits a planet. 3 Planet nearest to the sun.
6 The planet we live on. 4 Largest planet.
7 Farthest planet from the sun. 5 ―Shooting Star‖.
10 The sun and everything that travels
around it.
8 ―Paths‖ objects travel in around the sun.
9 Travels in long, cigar-shaped path around the
sun.
1 2 3
4
5
6 7 8
9
10
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What are the Outer Planets?
FILL IN THE BLANK
Complete each statement using a term or terms from the list below. Write your answers in the
spaces provided. Some words may be used more than once. (12 marks)
Voyager 1 Jupiter Neptune
Voyager 2 Saturn Uranus
gas giants Pluto
1. ________________________ is the largest planet.
2. The first planet known to have rings was .
3. ________________________and are bluish in colour.
4. Neptune, Uranus, Jupiter and Saturn are .
5. ______________________________ is the farthest planet from the sun right now.
6. ______________________________ is usually the farthest planet from the sun.
7. _______________________________and are spacecraft
that flew by Jupiter and Saturn.
8. _______________________________ also flew by Uranus and Neptune.
9. _______________________________is the smallest planet.
10. _______________________________was not visited by Voyager 1 or Voyager 2.
MATCHING
Match each term in Column A with its description in Column B. Put your answer in the Column
titled, Your Answer. You are to take the each letter beside an item in Column B and write it
beside the item in Column A that it is describing. (5 marks)
Your Answer Column A Column B
Io A moon of Pluto
Charon B moon of Saturn
Titon C volcanic moon of Jupiter
Triton D four Galilean moons
Ganymede, Calisto, Europa and Io E moon of Neptune
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Facts about the Earth’s Orbit
Moving Around the Sun
Though you can't feel it, Earth is always moving. It revolves around the sun. Look at the picture
below. The dotted line shows Earth's path around the sun. That path is called an orbit. Look at
the shape of Earth's orbit. It's like a flat circle. That shape is an ellipse.
Let's find out how Earth revolves! Obtain an apple or an orange, and spear it with a pencil. This
is your model earth and its axis. Rotate it around the "sun" which will be a bare light bulb. Look
carefully at the pictures below.
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CHANGING SEASONS
Earth has four seasons: summer, fall, winter, and spring. These seasons are always changing.
Summer changes into fall. Fall changes into winter. And winter changes into spring and spring
into summer. Why do you think seasons change? Here's why: The Earth tilts. And the Earth
revolves around the sun. As Earth revolves, the seasons change.
Look at picture A. It shows Earth when it's Summer in Canada.
Now look at picture B. Notice where Earth moves to. It is now Fall in Canada.
Look at picture C. Earth is halfway around the sun. It is it now Winter in Canada.
Look at Picture D. Earth has almost completed its trip around the sun. It is now Spring in
Canada.
The Moon: Earth's Satellite
The moon is a small planet. It's made of the same kinds of things that our planet is made of ---
rock and metals. The moon is Earth's satellite. A satellite always stays close to something that's
larger than it. Earth and the other eight planets are satellites of the sun.
Our moon always stays close to Earth. Earth is larger than the moon. Earth's gravity is strong; it
pulls on the moon. So, Earth's gravity keeps the moon close to Earth.
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The moon and Earth are both planets. But they don't look alike. Earth has oceans full of water.
The moon has no water on it. Earth has an atmosphere around it. The moon has no atmosphere at
all. The moon is a planet, as is Earth, but the moon shines. Where does its light come from?
Yes, the moon’s light comes from the sun! The sun lights up the moon.
You can try the following experiment, as shown in the picture to see how the sun lights up the
moon.
Materials you will need:
1. A globe of the world. (If you don’t have a globe, you can use a basketball or even a
cabbage.)
2. Get a lamp and position the lamp higher than the globe.
3. Make a model of the moon with a ball and a pencil.
Step1: Put the globe about 20 centimeters (or
12 inches) away from the lamp (your
sun). Turn on the lamp. Turn off all
other lights in the room and close the
curtains.
Step 2: Hold your moon model above the globe.
Look at that model. What happens to it?
One part of your model is lit up by the
lamp!
That's what happens to the moon. The sun shines on it and lights it up. We see the moon at night
because the sun lights it up.
The moon is like a dull mirror. It reflects the sun's light. And that light comes to Earth.
All planets reflect the sun's light. Suppose you were on the moon. The Earth would shine and
reflect the sun's light. Earth would shine like the moon!
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Does the Moon Have Gravity?
Picture this: you're in a spaceship that just landed on the moon. You're about to step out of that
spaceship. Can you walk on the moon? Or will you fly off into space?
You can walk on the moon. The moon has gravity. Its gravity will pull on you, so you won't fly
off into space. But as you walk on the moon, you'll feel lighter. That's because the moon's
gravity is weaker than Earth's. The moon has no atmosphere because its gravity is so weak that
it cannot hold an atmosphere around the moon.
Even though the moon’s gravity is weak, it pulls on the Earth. For example, it pulls on the
Earth’s oceans causing them to shift regularly: known as the tides coming in and out.
The moon is round, but it doesn’t always look round to us. Its shape seems to change because
the moon revolves around Earth.
Suppose the sun is behind the moon. The side of the moon facing the sun is lit by the sun. We
can't see that side because it faces away from earth.
The side that faces Earth is in darkness. We can't
see that side either. We say the moon then is a new
moon. (See picture A.)
As the moon revolves around Earth, it moves away
from the sun. We start seeing the side that's lit by
the sun. We see more of it as the moon revolves.
Soon we can see half of the side. We then say the
moon is a quarter moon. (See picture B.)
When the moon is halfway around Earth, we can
see all of the side that's lit. The moon's shape is
now round. We call that moon a full moon. (See
picture C.)
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Now the moon starts moving back toward the sun.
We see less and less of the side that's lit. Soon, we
see only half of it. (See picture D.) We say the
moon is a quarter moon, again.
When the moon completely revolves around Earth,
the sun is behind the moon again. (See picture E.)
What is the moon called now? We say the moon is
a quarter moon, again.
Another Way the Moon Moves
Do you know this? The same side of the moon always faces Earth. Why do you think this
happens? Find out why the same side of the moon always faces earth by doing the following.
Put a chair in the middle of a room. Face the front of your body to the chair. Now, slowly walk
around that chair. As you walk, keep the front of your body facing the chair.
What do you have to do to your body so that it always faces the chair? Right! You have to keep
turning your body so that it always faces the chair. You have to rotate your body.
Now, think about the moon. What does it do so that the same side always faces Earth? Right!
The moon rotates.
The Earth and the Moon
1. What is the name of the path the Earth takes around the sun? (1 mark)
2. Explain why the Earth experiences different seasons. (2 marks)
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3. Why do you think the moon stays close to the Earth? (2 marks)
4. The moon and the Earth are both planets, but they do not look alike. List two differences in
appearance between these 2 planets. (2 marks)
5. Explain why the moon has no atmosphere. (1 mark)
MATCHING
Match each term in Column A with its description in Column B. Put your answer in the Column
titled, Your Answer. You are to take the each letter beside an item in Column B and write it
beside the item in Column A that it is describing. (6 marks)
Your
Answer Column A Column B
The moon is A weaker than Earth’s gravity.
The moon shines because B it reflects the sun’s light.
The moon’s gravity is C Earth’s satellite.
Earth’s gravity holds the D shape seems to change.
The moon rotates as it E moon close to Earth.
As the moon revolves, it F revolves around the Earth.
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Lesson #10 What are Atoms
GLOSSARY OF TERMS
ATOMS
atom: smallest particle of a type of matter that has all of the same characteristics as that
type of matter.
electron: a part of the atom that has a negative electrical charge; orbits the nucleus
neutron: a part of the atom that has neither a positive or a negative charge; is found
in the nucleus.
nucleus: central part of an atom, which contains neutrons and protons
proton: a part of the atom that has a positive charge; is found in the nucleus
What are Atoms
What is the smallest thing you can think of? A single grain of sand? A particle of dust?
Now try to imagine something so small that you would need millions of them to make one grain
of sand! Imagine something so small that you cannot see it – not even with the most powerful
microscope.
There is something that small: the atom. All matter is made up of atoms. All solids. Liquids,
gases, and plasmas are made up of these tiny particles.
Atom are matter. One atom takes up space – very, very, very little space. An atom also has
mass – very , very, very little mass.
How small is the atom? Atoms are so small that in just one drop of water, there are about six
sextillion atoms.
That’s 6,000,000,000,000,000,000,000 atoms!!!
If you tried to count to six sextillion it would take you about one hundred trillion years – if you
counted fast!
The idea of the atom is far from new. Many year ago, before there were any ―real‖ scientists,
there were philosophers-people who did mental ―investigations.‖ They worked with ideas. Over
2,000 years ago, a Greek philosopher named Democritus, had the idea that all matter was made
up of tiny parts. He believed that these parts could not be divided or destroyed. He named them
atoms. In Greek, atomos means ―indivisible‖.
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Democritus could not prove this idea. He couldn’t even test it. So, it remained just an idea for
many years. Today, scientists have proven that many of Democritus’ ideas were correct.
Everyday, more and more is discovered about the atom.
Figure A:
Suppose each of those atoms were a
dope of water.
It would be six sextillion drops of
water
Figure B:
That’s more water than all the water that passes over
Niagara Falls in 2000 years.
Figure C:
That’s enough water to fill about six
billion Empire State Buildings
Figure D:
That’s almost twice as much water as there is in the
Mediterranean Sea.
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What are Atoms?
TRUE AND FALSE
Circle ―true‖ if the sentence is true, or ―false‖ is the sentence is false. (5 marks)
1. An atom is very large. True False
2. Democritus named the atom. True False
3. Solids are made of atoms. True False
4. Liquids are made of atoms. True False
5. Gases are not made of atoms. True False
MATCHING
Match each term in Column A with its description in Column B. Put your answer in the Column
titled, Your Answer. You are to take the each letter beside an item in Column B and write it
beside the item in Column A that it is describing. (5 marks)
Your Answer Column A Column B
Democritus A a very small particle
matter B Greek philosopher who named the atom
philosophers C made up of atoms
atomos D scholars who think about things
atom E Greek word for indivisible
Which is the smallest? Which is biggest?
Each group of words or terms below can be arranged by size. Write them in the correct order in
the space provided. (3 marks)
a piece of dust an elephant an atom
(smallest)
(largest)
a dime an atom a tip of a pin
(smallest)
(largest)
a rock a pebble an atom
(smallest)
(largest)
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Modern Atomic Theory
What is a synchrotron?
A synchrotron is device that accelerates
electrons to speeds approaching the speed of
light. These fast moving electrons emit a very
bright light as they orbit a central storage
ring. This synchrotron light is captured in
beamlines which can then be used in a
variety of ways to investigate the atoms and
molecules that make up everything around
us.
In the early 1800s, and English chemist named John
Dalton described his ideas about matter. Dalton’s
ideas were based on many scientific experiments and
observations. The ideas formed a theory that led to
our modern atomic theory.
You may wonder how we could know anything about a particle of matter that is too small to see
and almost too small to measure. Scientists have learned how to study atoms. They study atoms
by studying now matter behaves. They use very complicated equipment. However, you can
learn about atoms by studying what scientists have learned.
The present atomic theory states:
All elements are made up of tiny particles called atoms.
Atoms of a given element are alike.
Atoms of different elements are different
Chemical changes take place when atoms link up with, or separate from, one another.
Atoms are not created or destroyed by chemical change
Democritus was on the right track over 2000 years ago. However, one important part of his idea
has been proven wrong. Atoms are divisible. In fact the ―splitting‖ of the atom is the basis for
nuclear or atomic, energy.
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Modern Atomic Theory
STUDYING MODERN ATOMIC THEORY
FILL IN THE BLANK
Complete each statement using terms from the list below. Write your answers in the spaces
provided. Some words may be used more than once. (12 marks)
alike John Dalton atoms
created six sextillion indivisible
different small destroyed
Democritus 2000
1. The atom was first thought of by a man named more than
years ago.
2. In Greek, the word atomos means .
3. Matter that is indivisible cannot be .
4. An English chemist named presented a modern
atomic theory.
5. All elements are made of .
6. Atoms of a given element are all .
7. Atoms cannot be or
by chemical change.
8. Atoms of elements are different.
9. Atoms are so that we cannot see them.
10. There are atoms in a drop of water.
REACHING OUT
Why did it take 2000 years for scientists to confirm some of Democritus’ ideas about atoms?
(2 marks)
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What are the parts of an atom?
People once thought that the atom was the smallest particle of matter in the universe. However,
scientists now know that atoms are made up of even smaller parts. There are three different
kinds of particles. They are protons, neutrons and electrons.
Most of the mass of an atom is found in the central part of the atom, called the nucleus. The
nucleus of an atom is made p of protons and neutrons. These particles are packed very tightly
together in the nucleus.
Electrons are found outside the nucleus. They circle the nucleus very, very quickly. Electrons
are very small and have almost not mass. The number of electrons in an atom is always equal to
the number of protons in the nucleus of that atom.
Scientists have discovered that protons, electrons and neutrons have different charges. You
probably know that the word ―Charge‖ has something to do with electricity.
There are two kinds of charges. There are positive (plus) charges and negative (minus) charges.
By studying atoms, scientists have learned that:
Protons have positive (+) charges.
Electrons have negative (-) charges.
Neutrons have no charges. They are neutral
Since atoms have the same number of protons and electrons, the number of positive charges
equals the number of negative charges. The opposite charges cancel each other out. Therefore,
THE WHOLE ATOM HAS NO OVERALL CHARGE.
What the Parts of an Atom?
ATOMIC DIAGRAMS
The table below tells where the parts of the atom are found
and what the charge of each part is. (see Figure A).
Part Where Found Charge
proton inside nucleus +
neutron inside nucleus 0
electron outside nucleus -
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Figure B shows the centre of a lithium atom. The centre of an atom is called the nucleus.
(10 Marks)
1. Name the parts that make up its nucleus.
a) _______________________
b) _______________________
2. In the diagram, each ―p‖ stands for the word ____________
and each ―n‖ stands for ______________.
3. There are ______________protons in a lithium nucleus.
4. There are ______________neutrons in a lithium nucleus.
Figure C shows a full lithium atom.
5. How many electrons in a lithium atom? ______
6. How many positive charges in this atom? ______
7. How many negative charges in this atom? ______
8. What is the overall charge of this atom? ______
INTERPRETING ATOMIC DIAGRAMS
Below and on the following page are diagrams of sic different atoms. In the places provided to
the right of each diagram, fill in the number of protons, neutrons, electrons and positive charges
and the overall charge of each atom.
(3 Marks)
Protons
Neutrons:
Electrons:
Positive Charge:
Negative:
Overall Charge:
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(3 Marks)
Protons
Neutrons:
Electrons:
Positive Charge:
Negative:
Overall Charge:
(3 Marks)
Protons
Neutrons:
Electrons:
Positive Charge:
Negative:
Overall Charge:
(3 Marks)
Protons
Neutrons:
Electrons:
Positive Charge:
Negative:
Overall Charge:
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(3 Marks)
Protons
Neutrons:
Electrons:
Positive Charge:
Negative:
Overall Charge:
(3 Marks)
Protons
Neutrons:
Electrons:
Positive Charge:
Negative:
Overall Charge:
TRUE AND FALSE
Circle ―true‖ if the sentence is true, or ―false‖ is the sentence is false.
(5 marks)
1. A proton is found outside the nucleus. True False
2. A proton has a negative charge. True False
3. A neutron has a positive charge. True False
4. An electron has a negative charge. True False
5. An electron is found inside the nucleus. True False
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FILL IN THE BLANK
Complete each statement using a term or terms from the list below. Write your answers in the
spaces provided. Some words may be used more than once. (15 marks)
outside neutrons same
cancel out protons atoms
negative electrons nucleus
smaller no positive
1. All matter is made of tiny parts called .
2. The centre part of an atoms is called the .
3. A nucleus is made up of and
4. Electrons are found the nucleus.
5. Electrons are than protons or neutrons.
6. The main parts of an atom are , , and
.
7. Since protons have a charge, and neutrons have _____ charge,
the nucleus will have a charge.
8. Electrons have a charge.
9. An atom has the number of protons and electrons.
10. The plus and minus charges of an atom each other.