Introduction to Matter

Matter

• Anything that has mass and takes up space

– Solids

– Liquids

– Gases

Weight • A measure of the gravitational force exerted

on an object

• What is the difference between weight and mass?

• How do you measure weight?

– SPRING SCALES!

Mass

• The amount of matter in an object

• How do you measure mass?

– Balances!

• Dual Tray Balance

• Triple Beam Balance

Mass: The Measure of Inertia

• How hard would it be to push a large bus?

• How hard would it be to push a grocery cart?

Inertia

• The tendency of an object to resist a change in motion

• If an object is still, it tends to stay still

• If an object is moving, it tends to keep moving

How do we convert between weight and mass?

P. 8

Volume

• The amount of space taken up by an object

• How calculate for a rectangular prism?

Volume = length x height x width

• Check bell work…

Density

• Ratio of mass to volume

• A dense object has a large mass compared to a small volume

Physical Properties • What are some examples?

Physical properties are descriptions of characteristics

of objects that do not involve chemical change

Physical Properties

• Objects have physical properties

• Physical properties are descriptions of characteristics of objects that do not involve chemical change

• Unknown substances can be identified by their physical properties

Physical Properties

• Thermal

Conductivity

• State

• Density

• Ductility

• Malleability

• Color

• Odor

• Conductivity

• Solubility

• Hardness

• Luster

• Attracted to

magnet See page 11

Physical Changes

• A change in matter that does not result in chemical changes

• substance’s identity stays the same

• Examples:

– Change in state (Dissolving, Melting, freezing)

– Change in shape or volume

Chemical Property

• A description of a substance’s ability to take part in chemical reactions

Examples of Chemical Properties • Flammability

– The ability to catch on fire

• Reactivity – The ability of two or more substances to form a new

substance • Oxidation : A result of the ability of a substance to react

with oxygen

• Toxicity – The ability to be poisonous

• Sensitivity to Light

• Radioactivity

Chemical Changes • When one or more substances are changed into entirely NEW substances with different

properties

• Chemical Changes change the identity & composition of the matter involved – Physical changes do NOT

• Reactants are changed into products

Comparing Physical and Chemical Properties

• A physical property can be observed without changing the identity of the substance

• To observe a chemical property, the substance must undergo a chemical change

Matter and Chemical Change • Chemical Changes change the identity of the

matter involved

• Reactants are changed into products

What are SIGNS of a Chemical Change?

• Changes in color

• Changes in odor

• Changes in temperature (heat or cold)

• Bubbling, fizzing or foaming

• Sound or light given off

What Happens During a Chemical Change?

• Changes in physical properties

– What is seen, heard, felt, smelled?

• Changes in temperature

– Is heat energy absorbed or released?

• New substances form

– Did reactants create new products?

Density • What is happening here, in terms of

“particles of matter?”

Physical vs. Chemical Change

• Can the change be reversed?

– Physical changes can be easily reversed

• Examples?

– Chemical changes cannot be easily reversed

• Examples?

• Can they NEVER be reversed?

Comparing Physical and Chemical properties

• How can you tell the difference between a physical or a chemical property?

Physical vs. Chemical Change • Composition is the type of matter that makes up an

object

• Did the composition change?

• Physical changes do not change the composition of a substance

• Chemical changes do change the composition

Comparing Physical and Chemical Properties

• A physical property can be observed without changing the identity of the substance

• To observe a chemical property, the substance must undergo a chemical change

Examples of Chemical Changes

Are Examples of Chemical Changes Uncommon?

NO!

Characteristic Properties • The properties that are most useful in identifying a

substance

• Do not depend on sample size or amount

• Can be physical properties as well as chemical properties

• Examples: – Density, solubility (physical)

– Flammability, reactivity (chemical)

Endothermic vs. Exothermic

Energy IN

Energy OUT

Baking Soda & Vinegar Reactions

NaHCO3 + HC2H3O2 - NaC2H3O2 + H2CO3

(Baking Soda) (Vinegar or Acetic Acid) (Sodium Acetate) (Carbonic Acid)

“REACTANTS” “PRODUCTS”

What would be evidence of energy being transferred during reaction?

Baking Soda & Vinegar Reactions

Called a “Double Replacement” reaction

Different elements in two different compounds (reactants) replace each other

NaHCO3 + HC2H3O2 - NaC2H3O2 + H2CO3

(Baking Soda) (Vinegar or Acetic Acid) (Sodium Acetate) (Carbonic Acid)

Carbonic Acid immediately breaks down into H2O (water) and CO2 (Carbon Dioxide)

“REACTANTS” “PRODUCTS”

Tree Maps!

Physical

Properties 1. X

2. X

3. X

4. X

Changes 1. X

2. X

3. X

4. X

Chemical

Properties 1. X

2. X

3. X

4. X

Changes 1. X

2. X

3. X

4. X

Physical

Properties 1. Thermal Conductivity

2. State

3. Density

4. Ductility

5. Malleability

6. Color

7. Odor

8. Conductivity

9. Solubility

10. Hardness

11. Luster

12. Attracted to magnet

Changes (examples)

1.

2.

3.

4.

5.

6.

7.

8.

Chemical

Properties 1. Flammability

2. Reactivity

3. Oxidation

4. Toxicity

5. Sensitivity to Light

6. Radioactivity

Changes (examples)

1.

2.

3.

4.

5.

6.

7.

8.

What are SIGNS of a Chemical Change?

• Changes in color

• Changes in odor

• Changes in temperature (heat or cold)

• Bubbling, fizzing or foaming

• Sound or light given off

Characteristic Properties

• The properties that are most useful in identifying a substance

• They can be physical properties as well as chemical properties

• Examples may be physical OR chemical

– Density, solubility

– Flammability, reactivity

Change in state (melting,freezing,etc.)

Change in shape

Change in volume

Dissolving

Hot Gas

Rusting (“oxidation”)

Soured Milk

A Chemical Reaction

Matter

• Anything that has mass and takes up space

– Solids

– Liquids

– Gases

Mass

• The amount of matter in an object

• How do you measure mass?

– Balances!

• Dual Tray Balance

• Triple Beam Balance

Mass: The Measure of Inertia

• How hard would it be to push a large bus?

• How hard would it be to push a grocery cart?

Inertia

• The tendency of an object to resist a change in motion

• If an object is still, it tends to stay still

• If an object is moving, it tends to keep moving

How do we convert between weight and mass?

P. 8

Volume

• The amount of space taken up by an object

• How calculate for a rectangular prism?

Volume = length x height x width

• Check bell work…

Physical Properties

• Objects have physical properties

• Physical properties are descriptions of characteristics of objects that do not involve chemical change

• Unknown substances can be identified by their physical properties

Physical Properties • What are some examples?

Physical properties are descriptions of characteristics

of objects that do not involve chemical change

Let’s Review Physical Properties

• Thermal

Conductivity

• State

• Density

• Ductility

• Malleability

• Color

• Odor

• Conductivity

• Solubility

• Hardness

• Luster

• Attracted to

magnet See page 11

Let’s Review Physical Changes

• A change in matter that does not result in chemical changes

• substance’s identity stays the same

• Examples:

– Change in state (Dissolving, Melting, freezing)

– Change in shape or volume

Density • What is happening here, in terms of

“particles of matter?”

Density

• Ratio of mass to volume

• A dense object has a large mass compared to a small volume

Meniscus