• A A physical propertyphysical property is a characteristic is a characteristic that you can observe without changing or that you can observe without changing or trying to change the composition of the trying to change the composition of the substancesubstance.

• How something looks, smells, sounds, or How something looks, smells, sounds, or tastes are all examples of tastes are all examples of physicalphysical propertiesproperties.

Physical PropertiesPhysical Properties

• You can detect many You can detect many physical propertiesphysical properties with your senses. with your senses.

• For example, you can see the color and For example, you can see the color and shape of an object.shape of an object.

Using Your SensesUsing Your Senses

• You can also touch it to feel its texture. You can also touch it to feel its texture.

• You can smell the odor or taste the flavor You can smell the odor or taste the flavor of some matter. of some matter.

• To describe a sample of matter, you need To describe a sample of matter, you need to identify its to identify its statestate. This property, known . This property, known as the as the state of matterstate of matter, is another , is another physical physical propertyproperty that you can observe. that you can observe.

StateState

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• Perhaps you are most familiar with the Perhaps you are most familiar with the three states of water. three states of water.

StateState

• You can You can drink or drink or swim in swim in liquidliquid waterwater.

StateState

• You use the You use the solid statesolid state of water, which is of water, which is ice, when you put ice cubes in a drink.ice, when you put ice cubes in a drink.

• Although Although you can’t you can’t see it, water see it, water in the in the gasgas state state is all is all around you around you in the air.in the air.

• Some Some physical propertiesphysical properties depend on the depend on the size of the object. size of the object.

Size-Dependent PropertiesSize-Dependent Properties

• Another Another physicalphysical propertyproperty that depends that depends on size is on size is massmass, which , which is a measurement of is a measurement of how much matter it how much matter it contains. contains.

Size-Dependent PropertiesSize-Dependent Properties

• WeightWeight is a measurement of force. is a measurement of force.

Size-Dependent PropertiesSize-Dependent Properties

• If you were to travel to If you were to travel to other planets, your other planets, your weightweight would change would change but your but your sizesize and and massmass would not. would not.

• Weight Weight depends on the depends on the massmass of the object of the object and on and on gravitygravity. .

• Another physical property, Another physical property, densitydensity, does , does not depend on the size of an objectnot depend on the size of an object.

Size-Independent PropertiesSize-Independent Properties

• Density Density measures the amount of measures the amount of massmass in a in a given given volumevolume..

• To calculate the To calculate the densitydensity of an object, of an object, divide its divide its massmass by its by its volumevolume. .

• Another property, Another property, solubilitysolubility, also does not , also does not depend on size. depend on size.

Size-Independent PropertiesSize-Independent Properties

• SolubilitySolubility is the number is the number of grams of one of grams of one substance that will substance that will dissolve in 100 g of dissolve in 100 g of another substance at a another substance at a given temperature. given temperature.

• The temperature at which a solid changed The temperature at which a solid changed into a liquid is called its into a liquid is called its melting pointmelting point.

Melting and Boiling PointMelting and Boiling Point

• The temperature at The temperature at which a liquid which a liquid changes into a gas changes into a gas is called its is called its boilingboiling pointpoint. .

• Some materials pull iron toward them. Some materials pull iron toward them.

Magnetic PropertiesMagnetic Properties

• These materials are said to be magnetic. These materials are said to be magnetic.

• Lodestone is a rock that is naturally Lodestone is a rock that is naturally magnetic. magnetic.

• Some materials can be made into Some materials can be made into magnets. magnets.

• Some properties of matter cannot be Some properties of matter cannot be identified just by looking at a sample. identified just by looking at a sample.

Chemical PropertiesChemical Properties

• For example, the ability to burn is a For example, the ability to burn is a chemical propertychemical property. .

• A A chemical propertychemical property is a characteristic that is a characteristic that cannot be observed cannot be observed without altering the without altering the substance. substance.

Physical ChangesPhysical Changes• A A physical changephysical change is one in which the is one in which the

form or appearance of matter changes, but form or appearance of matter changes, but not its composition. For example, a not its composition. For example, a frozen lake has experienced a frozen lake has experienced a physicalphysical changechange. .

• Although the water Although the water changes states due to changes states due to change in temperature, change in temperature, it is still made of the it is still made of the elements hydrogen and elements hydrogen and oxygen. oxygen.

Changing ShapeChanging Shape

• Crumpling a sheet of paper into a ball Crumpling a sheet of paper into a ball causes a causes a physical changephysical change. .

• Whether it exists as one flat sheet or a Whether it exists as one flat sheet or a crumples ball, the matter is still paper. crumples ball, the matter is still paper.

• Generally, whenever you cut, tear, grind, Generally, whenever you cut, tear, grind, or bend matter, you are causing a or bend matter, you are causing a physicalphysical changechange. .

DissolvingDissolving

• When you add sugar to iced tea, the sugar When you add sugar to iced tea, the sugar only seems to disappear.only seems to disappear.

• Actually, the sugar Actually, the sugar dissolvesdissolves. .

• When this happens, the particles of sugar When this happens, the particles of sugar spread out in the liquid. spread out in the liquid.

• The The compositioncomposition of the sugar stays the of the sugar stays the same, which is why the iced tea tastes same, which is why the iced tea tastes sweetsweet.

• Only the form of the sugar has changed. Only the form of the sugar has changed.

Changing StateChanging State

• A A physical changephysical change occurs when matter occurs when matter changes from one state to another. changes from one state to another.

• When an ice cube melts, for example, it When an ice cube melts, for example, it becomes liquid water. becomes liquid water.

• Matter can change from any state to Matter can change from any state to another. another.

• FreezingFreezing is the opposite of melting. is the opposite of melting.

• During During freezingfreezing, a liquid changes into a , a liquid changes into a solid.solid.

Changing StateChanging State

• A liquid also can change into a gas. This liquid also can change into a gas. This process is known as process is known as vaporizationvaporization. .

• During the reverse process, During the reverse process, called called condensationcondensation, a gas , a gas changes into a liquid. changes into a liquid.

Changing StateChanging State

• In some cases, matter changes between In some cases, matter changes between the solid and gas states without ever the solid and gas states without ever becoming a liquid. becoming a liquid.

• The process in which a solid changes The process in which a solid changes directly into a gas is called directly into a gas is called sublimationsublimation. .

• The opposite process, in which a gas changes into a solid, is called deposition.

Chemical ChangesChemical Changes• The explosion of fireworks is an example The explosion of fireworks is an example

of a of a chemical changechemical change.

• During a During a chemical changechemical change, substances , substances are changed into different substances. are changed into different substances.

• In other words, the In other words, the composition of the composition of the substance changes. substance changes.

Chemical ChangesChemical Changes

• When iron in steel is exposed to oxygen When iron in steel is exposed to oxygen and water in air, iron and oxygen atoms and water in air, iron and oxygen atoms combine to form the principle component combine to form the principle component in rust. in rust.

• In a similar way, In a similar way, silver coins silver coins tarnish when tarnish when exposed to air. exposed to air.

Signs of Chemical ChangesSigns of Chemical Changes

• Physical changesPhysical changes are relatively easy to are relatively easy to identify. identify.

• If only the form of a substance changes, If only the form of a substance changes, you have observed a you have observed a physical changephysical change. .

• How can you tell whether a change is a How can you tell whether a change is a chemical changechemical change? ?

Signs of Chemical ChangesSigns of Chemical Changes

• You have witnessed a spectacular You have witnessed a spectacular chemical changechemical change if you have seen the if you have seen the leaves on a tree change from green to leaves on a tree change from green to bright yellow, red, or orange. bright yellow, red, or orange.

• But, it is not a change from a green But, it is not a change from a green pigment pigment to a red to a red pigmentpigment, as you might , as you might think. think.

• PigmentsPigments are chemicals that give leaves are chemicals that give leaves their color. their color.

Signs of Chemical ChangesSigns of Chemical Changes

• The green The green pigmenpigment that you see during the t that you see during the summer is summer is chlorophyllchlorophyll (KLOHR uh fihl). (KLOHR uh fihl).

• In autumn, however, changes in temperature and rainfall amounts cause trees to stop producing chlorophyll.

Signs of Chemical ChangesSigns of Chemical Changes

• The The chlorophyll chlorophyll already in the leaves already in the leaves undergoes a chemical change into undergoes a chemical change into colorless chemicals. colorless chemicals.

Signs of Chemical ChangesSigns of Chemical Changes• The The pigmentspigments that produce fall colors that produce fall colors

have been present in the leaves all along. have been present in the leaves all along.

• However, in the summer, However, in the summer, chlorophyllchlorophyll is is present in large enough amounts to mask present in large enough amounts to mask these these pigmentspigments. .

• In the fall, when In the fall, when chlorophyllchlorophyll production stops, the production stops, the bright bright pigmentspigments become visible. become visible.

ColorColor

• The reason a half-eaten apple turns brown The reason a half-eaten apple turns brown is that a is that a chemical changechemical change occurs when the occurs when the apple is exposed to air. apple is exposed to air.

• The color of food changes as it is cooked The color of food changes as it is cooked because a because a chemical changechemical change occurs. occurs.

EnergyEnergy

• Another sign of a Another sign of a chemical changechemical change is the is the release or gain of release or gain of energyenergy by an object. by an object.

• Many substances must absorb Many substances must absorb energyenergy in in order to undergo a order to undergo a chemical changechemical change. .

• For example, For example, energyenergy is absorbed during is absorbed during the the chemical changeschemical changes involved in involved in cooking. cooking.

EnergyEnergy

• Another Another chemical changechemical change in which a in which a substance absorbs substance absorbs energyenergy occurs during occurs during the production of cement. the production of cement.

• This process begins with the heating of This process begins with the heating of limestone.limestone.

• When it absorbs When it absorbs energyenergy during heating, it during heating, it undergoes a undergoes a chemical changechemical change in which it in which it turns into lime and carbon dioxide. turns into lime and carbon dioxide.

EnergyEnergy

• EnergyEnergy also can be released during a also can be released during a chemical changechemical change. .

• Fireworks release Fireworks release energyenergy in the form of in the form of light that you can see. light that you can see.

OdorOdor• When eggs and other foods spoil, they When eggs and other foods spoil, they

undergo undergo chemical changechemical change..• The change in odor is a clue to the The change in odor is a clue to the

chemical changechemical change..• When you smell an odd odor in foods, When you smell an odd odor in foods,

such as chicken, pork, or mayonnaise, such as chicken, pork, or mayonnaise, you know that the food has undergone a you know that the food has undergone a chemical changechemical change. .

• You can use this clue to avoid eating You can use this clue to avoid eating spoiled food and protect yourself from spoiled food and protect yourself from becoming ill. becoming ill.

Gases or SolidsGases or Solids• The formation of a The formation of a gasgas is a clue to a is a clue to a

chemical changechemical change..• The formation of a The formation of a solidsolid is another clue to is another clue to

a a chemical changechemical change. . • A A solidsolid that separates out of a solution that separates out of a solution

during a during a chemical changechemical change is called a is called a precipitateprecipitate. .

• A common A common precipitateprecipitate forms when a forms when a solution containing sodium iodide is solution containing sodium iodide is mixed with a solution containing lead mixed with a solution containing lead nitrate.nitrate.

Not Easily ReversedNot Easily Reversed

• PhysicalPhysical and and chemical changeschemical changes are are different from one another.different from one another.

• After solid ice melts into liquid water, it After solid ice melts into liquid water, it can refreeze into solid ice if the can refreeze into solid ice if the temperature drops enough. temperature drops enough.

• Freezing and melting are Freezing and melting are physicalphysical changeschanges. .

Not Easily ReversedNot Easily Reversed• The substances produced during a The substances produced during a

chemical changechemical change cannot be changed back cannot be changed back into the original substances by physical into the original substances by physical means. means.

• Wood that has changed into ashes and Wood that has changed into ashes and gases cannot be restored to its original gases cannot be restored to its original form as a log. form as a log.

• The substances that existed The substances that existed before the chemical before the chemical change no longer exist. change no longer exist.

Chemical Versus Physical ChangesChemical Versus Physical Changes

• In a In a physical changephysical change, the composition of a , the composition of a substance does not change. substance does not change.

• In a In a chemical changechemical change, the composition of , the composition of a substance does change.a substance does change.

• When a substance undergoes a When a substance undergoes a physicalphysical changechange, only its form changes., only its form changes.

• In a In a chemical changechemical change, both form and , both form and composition change. composition change.

Chemical Versus Physical ChangesChemical Versus Physical Changes

• When substances like wood and copper When substances like wood and copper undergo undergo physical changesphysical changes, the original , the original wood and copper still remain after the wood and copper still remain after the change. change.

• When a substance undergoes a When a substance undergoes a chemicalchemical changechange, however, the original substance is , however, the original substance is no longer present after the change. no longer present after the change.

Chemical Versus Physical ChangesChemical Versus Physical Changes

• Instead, different substances Instead, different substances are produced during the are produced during the chemical changechemical change. .

• When wood and copper When wood and copper undergo undergo chemical changeschemical changes, , wood and copper have changed wood and copper have changed into new substances with new into new substances with new physical and chemical physical and chemical properties. properties.

Chemical Versus Physical ChangesChemical Versus Physical Changes

• PhysicalPhysical and and chemical chemical changeschanges are used to recycle are used to recycle or reuse certain materials. or reuse certain materials.

Conservation of MassConservation of Mass

• During a During a chemical changechemical change, the form or the , the form or the composition of the composition of the mattermatter changes. changes.

• The particles within the The particles within the mattermatter rearrange rearrange to form new substances, but they are not to form new substances, but they are not destroyed and new particles are not destroyed and new particles are not created. created.

Conservation of MassConservation of Mass

• The number and type of particles remains The number and type of particles remains the same. the same.

• As a result, the total As a result, the total massmass of the of the mattermatter is is the same before and after a the same before and after a physicalphysical or or chemical changechemical change. This is known as the . This is known as the law of conservation of masslaw of conservation of mass. .

Conservation of MassConservation of Mass• In many In many chemical changeschemical changes in which in which massmass

seems to be gained or lost, the difference seems to be gained or lost, the difference is often due to a gas being given off or is often due to a gas being given off or taken in. taken in.

• If the gases could be If the gases could be contained in a chamber contained in a chamber around the candle, you around the candle, you would see that the would see that the massmass does not change. does not change.

Conservation of MassConservation of Mass• The scientist who first performed the The scientist who first performed the

careful experiments necessary to prove careful experiments necessary to prove that that massmass is conserved was is conserved was Antoine Antoine LavoisierLavoisier (An twan (An twan .. luh VWAH see ay) luh VWAH see ay) in the eighteenth century. in the eighteenth century.

• It was It was LavoisierLavoisier who recognized that the who recognized that the massmass of gases that are given off or taken of gases that are given off or taken from the air during from the air during chemical changeschemical changes account for any differences in mass. account for any differences in mass.

MATCHINGMATCHINGA.A. State State

J. Release of energyJ. Release of energyK. Mass K. Mass L. Liquid L. Liquid

I. Behavior I. Behavior H. Physical propertyH. Physical propertyG. Physical changeG. Physical change

F. Color F. Color E. Density E. Density D. Chemical propertyD. Chemical property

C. Chemical changeC. Chemical changeB. Boiling pointB. Boiling point

1. ___an indication that a chemical change 1. ___an indication that a chemical change has taken place.has taken place.

2. ___temperature at which liquid changes 2. ___temperature at which liquid changes to gas.to gas.

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MATCHINGMATCHINGA.A. State State

J. Release of energyJ. Release of energyK. Mass K. Mass L. Liquid L. Liquid

I. Behavior I. Behavior H. Physical propertyH. Physical propertyG. Physical changeG. Physical change

F. Color F. Color E. Density E. Density D. Chemical propertyD. Chemical property

C. Chemical changeC. Chemical changeB. Boiling pointB. Boiling point

3. ___a physical property of matter.3. ___a physical property of matter.

4. ___size, shape, or state of matter.4. ___size, shape, or state of matter.

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MATCHINGMATCHINGA.A. State State

J. Release of energyJ. Release of energyK. Mass K. Mass L. Liquid L. Liquid

I. Behavior I. Behavior H. Physical propertyH. Physical propertyG. Physical changeG. Physical change

F. Color F. Color E. Density E. Density D. Chemical propertyD. Chemical property

C. Chemical changeC. Chemical changeB. Boiling pointB. Boiling point

5. ___measure of how much of an object 5. ___measure of how much of an object there is.there is.

6. ___property that could be used to 6. ___property that could be used to indicate physical or chemical change.indicate physical or chemical change.

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MATCHINGMATCHINGA.A. State State

J. Release of energyJ. Release of energyK. Mass K. Mass L. Liquid L. Liquid

I. Behavior I. Behavior H. Physical propertyH. Physical propertyG. Physical changeG. Physical change

F. Color F. Color E. Density E. Density D. Chemical propertyD. Chemical property

C. Chemical changeC. Chemical changeB. Boiling pointB. Boiling point

7. ___melting is an example.7. ___melting is an example.

8. ___the ability to burn is an example8. ___the ability to burn is an example

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MATCHINGMATCHINGA.A. State State

J. Release of energyJ. Release of energyK. Mass K. Mass L. Liquid L. Liquid

I. Behavior I. Behavior H. Physical propertyH. Physical propertyG. Physical changeG. Physical change

F. Color F. Color E. Density E. Density D. Chemical propertyD. Chemical property

C. Chemical changeC. Chemical changeB. Boiling pointB. Boiling point

9. ___liquid, gas, or solid.9. ___liquid, gas, or solid.

10. ___how something acts.10. ___how something acts.

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MATCHINGMATCHINGA.A. State State

J. Release of energyJ. Release of energyK. Mass K. Mass L. Liquid L. Liquid

I. Behavior I. Behavior H. Physical propertyH. Physical propertyG. Physical changeG. Physical change

F. Color F. Color E. Density E. Density D. Chemical propertyD. Chemical property

C. Chemical changeC. Chemical changeB. Boiling pointB. Boiling point

11. ___a state of matter11. ___a state of matter

12. ___rusting of iron is an example12. ___rusting of iron is an example

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MULTIPLE CHOICEMULTIPLE CHOICE

13. ____Which of these is not a physical 13. ____Which of these is not a physical property of matter.property of matter.

A. Density A. Density

B. Mass B. Mass D. Texture D. Texture C. Ability to burnC. Ability to burnCC

14. ____An example of physical change 14. ____An example of physical change involving more than one substance is.involving more than one substance is.

A. Evaporating A. Evaporating

B. RustingB. Rusting

C. Burning C. Burning

D. Dissolving D. Dissolving DD

MULTIPLE CHOICEMULTIPLE CHOICE

15. ____an example of a change of state is15. ____an example of a change of state is

A. Evaporating A. Evaporating

B. Rusting B. Rusting

C. Burning C. Burning

AA

D. Dissolving D. Dissolving

MULTIPLE CHOICEMULTIPLE CHOICE

16. ____Which of the following shows a 16. ____Which of the following shows a behavioral property.behavioral property.

A. Peeling a bananaA. Peeling a banana

B. Iron attracted to a lodestoneB. Iron attracted to a lodestone

D. Hammer hitting a nailD. Hammer hitting a nail

C. Snow melting in the Sun.C. Snow melting in the Sun.

BB

MULTIPLE CHOICEMULTIPLE CHOICE

17. ____is an example of a chemical 17. ____is an example of a chemical change.change.

A. Melting of chocolate. A. Melting of chocolate.

B. Freezing of waterB. Freezing of water D. Burning of paperD. Burning of paperC. Salting of foodC. Salting of food

DD

18. ____which of the following is an 18. ____which of the following is an example of a chemical changeexample of a chemical change

A. Evaporating A. Evaporating

B. Melting B. Melting

C. Burning C. Burning

D. SublimationD. Sublimation

CC

MULTIPLE CHOICEMULTIPLE CHOICE

19. ____Which of these indicates that a 19. ____Which of these indicates that a chemical change has taken placechemical change has taken place

A. Change from a liquid to a gasA. Change from a liquid to a gas

B. Change in shapeB. Change in shape

D. Dissolving of a solidD. Dissolving of a solid

C. Release of heat energy.C. Release of heat energy.CC

MULTIPLE CHOICEMULTIPLE CHOICE

20. ____the density of a material is _____.20. ____the density of a material is _____.

A. How much the material weighsA. How much the material weighs

B. The mass of a unit volumeB. The mass of a unit volume

D. Whether or not the material floats in a D. Whether or not the material floats in a liquidliquid

C. How much space the material takes upC. How much space the material takes up

BB

MULTIPLE CHOICEMULTIPLE CHOICE

21. ____The process of a liquid changing 21. ____The process of a liquid changing into a gas is called_______.into a gas is called_______.

A. Sublimation A. Sublimation

B. Condensation B. Condensation D. Deposition D. Deposition C. Vaporization C. Vaporization CC

22. ____the process of a gas changing into 22. ____the process of a gas changing into a liquid is called________.a liquid is called________.

A. SublimationA. Sublimation

B. Condensation B. Condensation

C. Vaporization C. Vaporization

D. DepositionD. DepositionBB

23. ____The process of a solid changing 23. ____The process of a solid changing directly into a gas, without ever becoming directly into a gas, without ever becoming a liquid is called is called_______.a liquid is called is called_______.

A. Sublimation A. Sublimation

B. Condensation B. Condensation D. Deposition D. Deposition C. Vaporization C. Vaporization AA

24. ____the process in which a gas changes 24. ____the process in which a gas changes directly into a solid without ever directly into a solid without ever becoming a liquid is called________.becoming a liquid is called________.

A. SublimationA. SublimationB. Condensation B. Condensation

C. Vaporization C. Vaporization D. DepositionD. DepositionDD

MULTIPLE CHOICEMULTIPLE CHOICE

25. ____an objects odor _____.25. ____an objects odor _____.

A. Physical propertyA. Physical property B. Chemical propertyB. Chemical property D. Chemical changeD. Chemical changeC. Physical changeC. Physical change

AA

26. ____a change in an object’s odor is the 26. ____a change in an object’s odor is the result of a _____.result of a _____.

27. ____the precipitation of a solid can 27. ____the precipitation of a solid can indicate a _____.indicate a _____.

DDDD

SHORT ANSWERSHORT ANSWER

List 3 ways you could change the physical List 3 ways you could change the physical properties of the piece of paperproperties of the piece of paper

Crumpling the paperCrumpling the paper

Tearing the paperTearing the paper

Coloring the paperColoring the paper

Dissolving the paperDissolving the paper