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



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



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




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





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


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



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



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




Your


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


SNC2L Page 50

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



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


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



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





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



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





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




Your


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‖.


SNC2L Page 63

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


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





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)


SNC2L Page 65

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.


SNC2L Page 66

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)


SNC2L Page 67

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


SNC2L Page 71

FILL IN THE BLANK



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.

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