Chapter 3 Matter

I. Properties & Changes in Matter

Extensive vs.

Intensive

Physical vs.

Chemical

A. Extensive vs. Intensive

Extensive Property

depends on the amount of matter present

Intensive Property

depends on the identity of substance, not the amount

A. Extensive vs. Intensive

Examples:

boiling point

volume

mass

density

conductivity

intensive

extensive

extensive

intensive

intensive

B. Physical vs. Chemical

Physical Property

can be observed without changing the identity of the substance

Click for movie

Chemical Property

describes the ability of a substance to undergo changes in identity

B. Physical vs. Chemical

Examples:

melting point

flammable

density

magnetic

tarnishes in air

physical

chemical

physical

physical

chemical

B. Physical vs. Chemical

Physical Change

changes the form of a substance without changing its identity

properties remain the same

Chemical Changechanges the identity of a substanceproducts have different properties

B. Physical vs. Chemical Signs of a Chemical Change

change in color or odor

formation of a gas

formation of a precipitate (solid)

change in light or heat

B. Physical vs. Chemical

Examples:

rusting iron

dissolving in water

burning a log

melting ice

grinding spices

chemical

physical

chemical

physical

physical

Chemical verses physical changeWhich one is a physical change?

A. Sodium reacting B. Iodine changing with chlorine. from a solid to a gas

Matter

II. States of Matter

Kinetic Molecular Theory

States of Matter

Click for movie

Physical Properties

States of matter

solid liquid gas

A. Kinetic Molecular Theory

KMT

Particles of matter are always in motion.

The kinetic energy (speed) of these particles increases as temperature increases.

B. Four States of Matter

Solids very low KE - particles

vibrate but can’t move around

fixed shape fixed volume

B. Four States of Matter

Liquids low KE - particles can

move around but are still close together

variable shape fixed volume

B. Four States of Matter

Gases high KE - particles can

separate and move throughout container

variable shape variable volume Click for movie

The States of Matter

VAPORIZATION

CONDENSATIONMELTING

FREEZING

Changes of State

Melting - the transition from the solid substance into a liquid The melting Point

Freezing or Fusion - liquid to solid The Freezing point

When does water melt? When does water freeze?

Changes of State

Boiling or Vaporization or Evaporation

liquid to gas Condensation - gas to liquid

Sublimation - solid to gas Deposition - gas to solid

B. Four States of Matter

Plasma very high KE - particles collide with

enough energy to break into charged particles (+/-)

gas-like, variableshape & volume

stars, fluorescentlight bulbs, CRTs

Matter

III. Classification of Matter

Matter Flowchart

Pure Substances

Mixtures

A. Matter Flowchart

MATTER

Can it be physically separated?

Homogeneous Mixture

(solution)

Heterogeneous Mixture Compound Element

MIXTURE PURE SUBSTANCE

yes no

Can it be chemically decomposed?

noyesIs the composition uniform?

noyes

Colloids Suspensions

A. Matter Flowchart

Examples:

graphite

salt & pepper

sugar (sucrose)

paint

soda

element

hetero. mixture

compound

hetero. mixture

solution

B. Pure Substances

Element composed of identical atoms Ex: copper wire, aluminum foil

B. Pure Substances

Compound

composed of 2 or more elements in a fixed ratio

properties differ from those of individual elements

Ex: table salt (NaCl)

B. Pure Substances

Law of Definite Composition

A given compound always contains the same, fixed ratio of elements.

Law of Multiple Proportions

Elements can combine in different ratios to form different compounds.

B. Pure Substances

For example…

Two different compounds, each has a definite composition.

C. Mixtures

Variable combination of 2 or more pure substances.

Heterogeneous Homogeneous

C. Mixtures

Solution homogeneous very small particles no Tyndall effect Tyndall Effect

particles don’t settle EX: rubbing alcohol

C. Mixtures

Colloid heterogeneous medium-sized particles Tyndall Effect particles don’t settle EX: milk

C. Mixtures

Suspension heterogeneous larger particles Tyndall Effect particles settle EX: fresh-squeezed

lemonade with pulp

Heterogeneous Mixtures

Heterogeneous mixtures occur when you can see the physical differences between the substances.

Is a salt and water mixture a heterogeneous mixture?

Is a mixture of sand and water a heterogeneous mixture?

Rubbing Alcohol

Oil

Corn syrup

C. Mixtures

Examples:

milk

muddy water

fog

salt & water

Italian salad dressing

colloid

suspension

colloid

solution

suspension

Physical Separation Techniques

Mixtures are combinations of two or more substances that when mixed do not change.

Therefore, physical properties can be used to separate them.

What physical properties could be used? Think about how you could separate iron,

salt and sand. Total Cereal

Physical Separations

Filtering Separation by the

physical property of solubility. One substance is soluble the other is not.

Coffee filters Tea bags Spaghetti

Physical Separations

Chromatography Separation by

solubility, mass or bonding properties

Separation of inks Separation of M&M

dyes Separation of leaf

pigments.

Physical Separations

DistillationSeparation by

the physical properties of melting point or boiling point

Purifying water