What’s the MATTER:Classify Changes of Matter

Matter, Classify Changes of Matter

At the conclusion of our time together, you should be able to:

1. Characterize various changes of matter2. Recognize that a change of state in

matter is a physical change

Interesting Signs:

PhysicalPhysical

Physical ChangePhysical Change

A change in matter from one form to another without changing its chemical properties

(most can be reversed)No change in atoms/molecules

Physical Change

Examples = Change in state or phase change Dissolving Compressing Light emission/absorption Electrons passing through metals

Physical Change

More Examples =

boiling of a liquid melting of a solid dissolving a solid in a

liquid to give a homogeneous mixture

making a solution

ChemicalChemical

Chemical ChangeChemical Change

Bonds are made / broken Change in oxidation states Bonds are made / broken Change in oxidation states

Cl-1 Cl-1

21

Li +1

Examples of Chemical Change

Chemical change or chemical reaction — transformation of one or more atoms or molecules into one or more different molecules.

• Burning hydrogen (H2) in oxygen (O2) gives H2O.

Sure Signs of a Chemical Change“Chemists Get Practice Trying Labs”

Color Change Gas Produced (not from

boiling!) Precipitate – a solid

formed by mixing two liquids together

Temperature Change Light

Will This be on the Test????

Remember the Law of Conservation of Mass

In a physical change or a chemical reaction, mass is neither created or destroyed

(Antoine Lavoisier)

Matter, Classify Changes of Matter

Let’s see if you can:

1. Characterize various changes of matter2. Recognize that a change of state in

matter is a physical change

Physical vs. Chemical Change

Examples:

melting

flame produced

paper cut

dissolving salt

in water

tarnishes in air

physical

chemical

physical

physical

chemical

Examples:

rusting iron

mixing mud and

water

burning a log

freezing water

grinding spices

Physical vs. Chemical Change

chemical

physical

chemical

physical

physical

A difference between physical change and chemical change is that

1. chemical change involves energy while physical change does not.

2. physical change involves energy while chemical change does not.

3. different kinds of molecules are present after a physical change but not after a chemical change.

4. different kinds of molecules are present after a chemical change but not after a physical change

In making a pizza, which process involves a chemical change?

1. Mixing spices for the sauce

2. Slicing pepperoni for the topping

3. Spreading cheese on the pizza

4. Baking the dough to form the crust

In making a pizza, which process involves a chemical change?

1. Mixing spices for the sauce

2. Slicing pepperoni for the topping

3. Spreading cheese on the pizza

4. Baking the dough to form the crust

All You Really Need To Know You Can Learn From Noah's Ark

11. Remember that the ark was built by amateurs; the Titanic was built by professionals.

12. Remember that woodpeckers inside are a larger threat than the storm outside.

What’s the MATTER, Properties of Matter

Matter, Properties of Matter

At the conclusion of our time together, you should be able to:

1. Explain the difference between the extensive and intensive properties and other types of properties

2. Distinguish between a physical property and chemical property

Too late to learn this stuff???

The Nature of MatterThe Nature of Matter

Chemists are interested in the nature of matter and how this is related to its

atoms and molecules.

Gold Mercury

Chemistry & Matter

We can explore the MACROSCOPIC world — what we can see —

to understand the PARTICULATE worlds we cannot see.

We write SYMBOLS to describe these worlds.

A Chemist’s View

2 H2(g) + O2 (g) --> 2 H2O(g)

MacroscopicMacroscopic

SymbolicSymbolic

ParticulateParticulate

Septic Tank Humor

Properties of Matter

2 Types:

Extensive – depend on the amount of the sample

Always involves a number with unit Examples = volume

masslength

Properties of Matter (cont.)

Intensive – does not depend on the amount of the sample

Usually does not involve a number Examples = density

melting, boiling point

malleabilityductilitycolorodor

Properties

Every substance has a unique set of properties (characteristics that identify that substance)

Physical Properties- Properties that can be measured

without changing the identity and composition of the substance

Physical Property Examples-

Color Odor Density Melting Point Boiling Point Hardness Solubility

A Stick

What Do You Call a Boomerang That Doesn't Work?

Graphite — this layer structure of carbon atoms reflects its physical properties.

List Some Physical Properties of:

Chemical Properties

Properties that describe the way a substance may change to form other substances

Only observed when a chemical reaction takes place

Chemical Property Examples

Combustible Reactive with water or acid Flammable Corrosive Decomposes in air

Do I Have to Learn this Stuff???

Physical vs. Chemical Properties

Physical Properties- Properties that can be measured

without changing the identity and composition of the substance

Chemical Properties- Properties that can be measured by

changing the identity and composition of the substance

Matter, Properties of Matter

Let’s see if you can:

1. Explain the difference between the extensive and intensive properties and other types of properties

2. Distinguish between a physical property and chemical property

Design a Hypothesis

Properties of Matter

2 Types:

Extensive – depends on the amount of the sample Intensive – does not depend on the amount of the

sample

Physical vs. Chemical Properties

Physical Properties- Properties that can be measured

without changing the identity and composition of the substance

Chemical Properties- Properties that can be measured by

changing the identity and composition of the substance

Physical vs. Chemical Property

Examples:

melts at 55oF

flammable

will tear easily

will dissolve in

water

will tarnish

physical

chemical

physical

physical

chemical

Examples:

will rust

mixture can be

separated by boiling

burns

freezes at -20oC

can be crushed

Physical vs. Chemical Properties

chemical

physical

chemical

physical

physical

Familiar Saying

A rotating lithoidal fragment never accrues lichen.

A rolling stone gathers no moss!!

Oobleck Time!!

The End!!!