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Grade 9 Science

Unit 1

Atoms, Elements, & Compounds

Name:

Homeroom #:

Chapter 1: Atomic theory explains the composition and behavior of matter.

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Lab Safety

Complete Poster on Lab Safety

WHMIS

W

H

M

I

S

WHMIS Symbols:

Hazard Symbols:

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Properties of Matter

Matter is anything that has and .

Mass is the amount of in a substance or object.

Volume is the a substance or object occupies.

Matter is made up of .

Elements are substance that ________________________________________________

_______________________________________________________________________

_______________________________________________________________________.

Describing Matter

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Physical Properties Chemical PropertiesDefinition

Characteristics of matter that are often ______________ or _______________.

Can be either ___________________ (observed) or

(measured).

Observed when substances ______________ with each other.

Determines a substances’ ________________.

Examples

WHMIS and Safety Worksheet

A B C D E F G H

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1. What does WHMIS stand for?

2. What is the purpose of WHMIS?

3. What information would you find on a WHMIS label?

4. Do all products and chemicals have WHMIS labels? Explain.

5. Identify the following symbols, write down at least one hazard this symbol represents and give one example of a material or chemical that may have this symbol.

Identify Symbol One Hazard Example

A

B

C

D

E

F

G

H

6.

E

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What is an MSDS, and what kind of information would be found on it?

7. Identify the following International Safety Symbols. A

B

C A B C

D

E

F

D F G

H

I

J ____________________ G H I

J K L

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Core Lab Activity 1-2C pg. 20

Chemical and Physical Properties

Name: ______________________________

Aluminum Magnesium Iron Copper Zinc

Chemical symbol

PROPERTY

Luster before polishing with sandpaper

(lustrous or dull)

Luster after polishing

(high, medium, or dull)

Malleability

(high or low)

Magnetism

(yes or no)

Electrical conductivity

(yes or No)

Reactivity to acid

(yes or no)

Reactivity to air when heated

(high, medium, or low)

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Analyze:

PROPERTY

Is this a physical property or a chemical property?

Do all of the metals have this property (to some degree)?

Yes or No

Luster

Malleability

Magnetism

Electrical conductivity

Reactivity to acid

Reactivity to air when heated

Conclude and Apply:

1. What is the definition of a physical property? ______________________________________________________________

__________________________________________________________________

Name all the physical properties these metals had in common.

______________________________________________________________

2. What is the definition of a chemical property? ______________________________________________________________

__________________________________________________________________

Name all the chemical properties these metals had in common.

_________________________________________________

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Theory vs. Law

A theory is _______________________________________________

Theories ________________________________________________________________

For example:

Most laws are _

__________________________________________________________________ .

For example:

Atomic Theory

The descriptions of __________ .

Atomic Theory has ________________________________________________________

________________________________________________________________________

Early Ideas… 2000 years ago

o Empedocles said that matter was composed of the four “elements”;

, , &

o Democritus : _______________________________________________________

________________________________________________________________________

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Development of the Atomic Theory

Scientist Ideas Diagram of ModelJohn Dalton(1766-1844)

Model Name:

J.J. Thomson(1856-1940)

Model Name:

ideas diagram

Ernst Rutherford(1871-1937)

Model Name:

ideas diagram

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Niels Bohr(1885-1962)

Model Name:

ideas diagram

Inside the Atom

Subatomic Particle Charge Mass Location

Proton (p+)

Neutron (n0)

Electron (e-)

The Atom

Label the diagram:

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Complete this concept map for the parts of an atom. Use each of the following terms:

electron, negatively charged, neutron, proton, nucleus, positively charged

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Chapter 1:Atomic theory explains the composition and behaviour of matter.

1. Matter can be defined as anything that has two particular physical properties. What arethese properties?

____________________________ and ___________________________

2. What happens in a chemical change?

_____________________________________________________________________________________

3. What happens in a physical change?

_____________________________________________________________________________________

4. Explain the term combustibility.

_____________________________________________________________________________________

5. Provide an example of a chemical and a physical property of aluminum.

Chemical: ______________________________________________________________

Physical: _______________________________________________________________

6. Classify the following as chemical or physical properties:

(a) Cotton balls are soft. ______________________________

(b) Water boils at 100°C. __________________________________

(c) Diamonds can be used to cut glass. ________________________

(d) Sugar dissolves in water. ________________________________

(e) Propane is a gas. ______________________________________

(f) Propane burns in air. ___________________________________

7. Water and gasoline are both clear liquids at room temperature. Describe one physical property and one chemical property that might be used to distinguish between them.

Chemical: _______________________________________________________________________

Physical: _________________________________________________________________________

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11. What does each of the following terms mean?

(a) malleability ____________________________________________________________________

(b) boiling point _____________________________________________________________________

(c) ductility __________________________________________________________________________

(d) conductivity _______________________________________________________________________

(e) solubility __________________________________________________________________________

(f) texture ____________________________________________________________________________

(g) viscosity __________________________________________________________________________

12. Which physical property is the ratio of the mass of a substance divided by its volume?

_______________________________________

13. Select any four of the physical properties listed in Table 1.1 on page 18 and use them to describe:

(a) gold ______________________________________________________________________

______________________________________ ________________________________

(b) sugar _____________________________________________________________________

______________________________________ ________________________________

(c) water _____________________________________________________________________

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______________________________________ ________________________________

14. What was the main goal of the alchemists?

____________________________________________________________________________________

15. What was the difference between Dalton’s model of the atom and Thomson’s model?

_____________________________________________________________________________________

_____________________________________________________________________________________

16. What did Rutherford discover in his gold foil experiment?

_____________________________________________________________________________________

_____________________________________________________________________________________

17. What was the difference between Thomson’s model of the atom and Rutherford’s model?

_____________________________________________________________________________________

_____________________________________________________________________________________

18. What did Bohr discover about how electrons are arranged in atoms? _____________________________________________________________________________________

_____________________________________________________________________________________

19. What type of charge does the nucleus have? _______________________________

20. What type of charge do electrons have? ___________________________________

21. What are two properties that protons and electrons have in common?

_____________________________________________________________________________________

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22. Which two subatomic particles are nearly equal in mass? _______________ and ________________

23. Which part of an atom accounts for most of its volume? -__________________________

24. What is the difference between a theory and a law?

_____________________________________________________________________________________

_____________________________________________________________________________________

25. How are new theories developed?

_____________________________________________________________________________________

_____________________________________________________________________________________

26. Neutral atoms have no overall electric charge even though protons and electrons have an electric charge. Explain.

_____________________________________________________________________________________

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Key Term Definition

______ 1. atom A. the amount of matter in a substance or object (often measured in grams)

______ 2. atomic theory B. ratio of material’s mass to its volume

______ 3. boiling point C. degree to which the substance combines chemically with other substances (water, acid, other substances)

______ 4. chemical properties D. a particle with a positive electric charge

______ 5. combustibility E. a smaller particle (proton, neutron, electron) within the atom

______ 6. conductivity F. the amount of space a substance or an object occupies (often measured in litres)

______ 7. density G. tiny, dense, positively charged centre of the atom

______ 8. electron H. characteristics of matter that are often observed or measured

______ 9. element I. degree to which the substance burns (reacts with air or pure oxygen)

______10. hazard symbol J. the smallest particle of an element that retains the properties of the element

______11. mass K. a system used to ensure that everyone has access to appropriate safety information about any hazardous substance they may encounter that is manufactured and sold

______12. matter L. temperature of boiling/condensing

______13. melting point M. a symbol that provides two kinds of safety warnings

______14. neutron N. a substance that contains only one kind of matter and cannot be broken down or separated into simpler substances

______15. nucleus O. various descriptions of matter and how it behaves

______16. physical properties P. negatively charged particles

______17. proton Q. a particle with no electric charge

______18. reactivity R. anything that has mass and volume

______19. state S. characteristics that can be observed when substances react with each other

______20. subatomic particle T. solid, liquid, gas

______21. volume U. ability to conduct electricity or heat

______22. WHMIS V. temperature of melting/freezing

Grade 9 Science Summary Chapter 1

Atomic theory explains the composition and behaviour of matter.1. Safety in the science classroom

Make safety your first priority.

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Know the rules before starting a lab, and follow safe procedures while doing a lab.

Know what to do in case of an emergency. Recognize WHMIS and other safety hazard symbols.

2. Properties of Matter

• Physical properties are characteristics of matter that can be observed or measured for a single substance.

• Chemical properties are characteristics of matter that can be observed only when substances react chemically.

• Qualitative properties can be described, while quantitative properties can be measured.

• Some qualitative properties include state, colour, malleability, ductility, texture, luster and magnetism.

• Some quantitative properties include solubility, conductivity, viscosity, density, melting point, and boiling point.

3. Models of the Atom• In Dalton’s model, atoms are indivisible, differ between elements, and can combine to form new compounds.

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• In Thomson’s model, the atom is composed of negative and positive charges.

• In Rutherford’s model, the atom has a dense, positively charged nucleus, surrounded by electrons.

• In Bohr’s model, the electrons occupy energy levels in regions surrounding the nucleus.

4. Subatomic Particles in the Atom• Atoms are composed of three subatomic particles called protons, neutrons, and electrons.

• Most of the mass of the atom is contained in the nucleus by protons (positive) and neutrons (neutral).

• Most of the volume of the atom is occupied by electrons (negative), which occupy energy levels near the nucleus.

Chapter 1 Practice QuizCircle the letter of the best answer.

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 1. Which of the following hazard label symbols warn that the chemical is poisonous?I. II.

III. IV.

A. I and IIB. II and IVC. I, II, and IVD. IV only

 2. If a fire erupts in the laboratory, what should you do first?A. Call out “Fire!”B. Get a fire extinguisher.C. Throw water on the fire.D. Pull the evacuation alarm.

 3. Personal prescription eyeglasses provide as much protection asA. a face shieldB. safety gogglesC. safety glassesD. sunglasses

 4. Which is a chemical propertyA. densityB. ductilityC. magnetismD. toxicity

 5. Which term describes the temperature at which a solid turns to a liquid?A. boiling point

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B. melting pointC. reactivityD. temperature

 6. Which physical property can be measured numerically?A. colourB. densityC. lustreD. malleability

 7. J. J. Thomson discovered that all atoms contain particles that later became known as electrons. What did this discovery make it possible to conclude about atoms?A. All atoms are composed of a combination of subatomic particles.B. All atoms are identical to all other atoms.C. All atoms are negatively charged.D. All atoms conduct electricity.

 8. Which best describes the nucleus?A. contains neutrons and electrons; negatively chargedB. contains protons and electrons; electrically neutralC. contains protons and electrons; positively chargedD. contains protons and neutrons; positively charged

 9. Which best describes an atom?A. electrically neutralB. positively chargedC. negatively chargedD. positively or negatively charged

Match the Term on the left with the best Descriptor on the right.Each Descriptor may be used only once.

Term Descriptor

_____ 10. nucleus_____ 11. electron_____ 12. conductive_____ 13. density_____ 14. neutron_____ 15. malleable

A. a subatomic particle with a charge of zeroB. dense part of an atomC. able to be drawn into a wireD. able to transmit heat or electricityE. occupies an energy level surrounding the

nucleusF. change in state from liquid to gasG. able to be hammered into a sheetH. ratio of mass to volume I. a measure of hardness

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Short Answer Questions16. Provide one reason for why we have each of the following safety rules.

(a) Always work under supervision and only on approved activities.________________________________________________________________

________________________________________________________________

(b) Wear your safety eyewear in the lab as long as any chemicals are still being used, even if you are finished your own work.________________________________________________________________

________________________________________________________________

(c) Do not eat, drink, or chew gum in the lab.________________________________________________________________

________________________________________________________________

17. (a) Dalton’s atomic theory says that all matter is made of small particles called atoms..Use Dalton’s theory to explain why a piece of copper cannot be turned into piece of gold._______________________________________________________________

_______________________________________________________________

(b) Rutherford’s model of the atom resulted from an experiment in which alpha particles were made to pass through a thin gold sheet. Most alpha particles passed straight through, but some were deflected. Explain what Rutherford was able to conclude from this about the composition of atoms._______________________________________________________________

_______________________________________________________________

(c) Bohr studied the results of experiments on the light released by gaseous samples of atoms, such as those of hydrogen. What was he

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able to conclude from this about the way electrons exist in atoms?_______________________________________________________________

18. (a) Where is 99.99% of the mass in an atom located?________________________________________________________________

(b) Which particles in an atom occupy 99.99% of the volume of the atom?________________________________________________________________

(c) Where is all of the positive charge in an atom located?________________________________________________________________