Provide the following information on the slip provided

• Name …the one you want to be called.

• Code name…a clean one…I will use this to post your grades.

• Indicate if you require a front desk …include if the reason is for vision.

Info sheet 2

The science that deals with the structure and behavior of matter

Unit I Classification of Matter

• Chemistry –

- the study of matter and its changes.

• Matter –

– anything that has substance and takes up space.

• Data is gathered by investigation and observation.

• Observations are statements of fact

• 2 kinds of observations

Quantitative

– involves measurement (numbers)

Qualitative

– all the rest

Physical & Chemical Properties Physical & Chemical Changes

How to determine if an observation is Physical or Chemical

Ask the question; “ Is new matter being formed?”

If the answer is YES………

CHEMICAL

If the answer is NO………

PHYSICAL

How to determine is the observation is a change or a property.

If the verb ends in “ing” …..

CHANGE

If the verb does not end in “ing”…….

PROPERTY

Note: All phase changes are physical changes

• Physical properties – color, hardness, texture, phases, density, ability to conduct heat, electricity.

• When a physical change occurs a physical property will be different. For example, melting ice.

heatHeat

Ca O Ca SS8 O2

Chemical change – a substance changes from one type of matter to another.

Describe each of the following as a Physical Property, Physical Change, Chemical Property or Chemical Change

1. Moth balls melt at 56.0 oC.

2. Material “A” exists as a yellow powder.

3. A plant growing.

4. Crushing rock.

5. Propane burns in air.

6. Water condenses at 100 oC.

7. HCl(aq) is neutralized when it reacts with NaOH(aq).

8. Breaking a piece of Chalk.

Describe each of the following as a Physical Property, Physical Change, Chemical Property or Chemical Change

1. Moth balls melt at 56.0 oC. PP

2. Material “A” exists as a yellow powder. PP

3. A plant growing. CC

4. Crushing rock. PC

5. Propane burns in air. CP

6. Water condenses at 100 oC. PP

7. HCl(aq) is neutralized when it reacts with NaOH(aq). CP

8. Breaking a piece of Chalk. PC

A cube of table sugar is dissolved in de-mineralized water. Classify (describe) this

sample of matter using as many terms as you can.

• Solution• Mixture• Liquid (solid, gas)• Homogeneous (heterogeneous)• 2 compounds (water and sugar) (element)• Non – electrolyte (electrolyte)• Neutral (acid, base)• Molecules (ions)

• C12H22O11 (aq)

Definitions

Homogeneous

- sample is uniform throughout (same physical and chemical properties)

Heterogeneous

- non uniform mixture; you can see individual parts of the mixture. That is – parts have different chemical and physical properties.

Pure substances

- samples of matter that have a definite set of physical and chemical properties. (elements or compounds)

Mixtures

- a combination of substances that have no definite or fixed proportions.

Solutions

- homogeneous mixtures

Elements

- a pure substance that cannot be broken down into different kinds of matter. (contains only one kind of atom)

Compounds

- elements chemically combined in definite proportions.

Elements

Compounds vs Mixtures

Compounds Mixtures

Components lose their identities. (C & P properties)

Components retain their identities. (C & P properties)

Components are present in fixed proportions.

Components may be present in any proportion.

Components can be separated by chemical means only.

Components can be separated by simple physical process.

Evidence of chemical action during preparation. (heat, light, color change etc)

No evidence of chemical action during preparation

A Classification Scheme

Matter

Homogeneous Heterogeneous

mixturePure substances

Elements

mixtures

Metals

compounds

Non metals

solutions

Bar of zinc

C3H8(g)

glass of 7-up

Shovel of dirt from the field

Helium gas

NaHCO3 dissolved in water

Gold coin

Complete the following table by placing an ‘x’ for all that apply

elem

ent

solu

tio

n

com

po

un

d

mix

ture

Ho

mo

gen

eou

s

Het

ero

gen

eou

s

met

al

?

Sample of Matter

Bar of zinc x x x

C3H8(g) x x

glass of 7-up x x x

Shovel of dirt from the field x xHelium gas x xNaHCO3 dissolved in water x x x

Gold coin x x x

Complete the following table by placing an ‘x’ for all that apply

elem

ent

solu

tio

n

com

po

un

d

mix

ture

Ho

mo

gen

eou

s

Het

ero

gen

eou

s

Met

al ?Sample of Matter

Kinetic Molecular Theory (KMT)

1. We believe that all molecules are in a state of constant motion.

2. Three kinds of motion are possible:

A) Vibrational – back and forth

B) Rotational – spinning on an axis

C) Translational – movement through space

3. We use this theory to explain the states (phases) of matter.

Solids Liquids GasesMolecules vibrate Molecules vibrate

and rotateMolecules vibrate, rotate and translate

Definite shape Shape of the container

Shape of the container

Definite volume Definite volumeExpand to occupy all the available space

High attractive forces between molecules

Weak attractive forces between molecules

Very weak attractive forces between molecules

Molecules very close together

Molecules very close together Molecules very far apart

Orderly arrangement of molecules

Molecules very dis-organized

More orderly than gases but less than solids

Not very compressible Not very compressible Very compressible

Heating of a solid

Temp.

(oC)

Time (s)

A

B C

D E

F

A → B : Heating of a solidB → C : Melting of a liquid (Phase change)C → D : Heating of a liquidD → E : Evaporating a liquid (Phase change)E → F : Heating of a gas (closed system)

Phase ChangesGAS

LIQUID

SOLID

1

2 3

4

5 6

1. Condensation

2. Freezing

3. Melting

4. Evaporation

5. Sublimation

6. Sublimation