States of Matter

Chapter 2:Chapter 2:Matter & ChangeMatter & Change

I. States of Matter

– Kinetic Molecular Theory

– States of Matter

A. Kinetic Molecular TheoryA. Kinetic Molecular Theory

KMT

– Matter is made of tiny particles

– Particles of matter are always in motion.

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

B. Four States of MatterB. Four States of MatterSolids

– very low KE - particles vibrate but can’t move around

– fixed shape

– fixed volume

– Not easily compressed

B. Four States of MatterB. Four States of MatterLiquids

– low KE - particles can move around but are still close together

– variable shape (that means they take the shape of the container)

– fixed volume– Not easily compressed

B. Four States of MatterB. Four States of MatterGases

– high KE - particles can separate and move throughout container

– variable shape (that means they take the shape of the container)

– variable volume (that means it will expand to fit the size of its container)

– Easily compressed

B. Four States of MatterB. 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, flat screen TVs

Quickie QuestionsQuickie Questions

This theory says particles are always in motion?

What are the four states of matter?

What state of matter has fixed volume and shape?

What state of matter consists of charged particles

Kinetic Molecular Theory

Solid, Liquid, Gas, Plasma

Solid

Plasma

Ch. 2 Matter & ChangeCh. 2 Matter & Change

II. Classification of Matter

–Matter Flowchart

–Pure Substances

–Mixtures

Matter FlowchartMatter 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 FlowchartA. Matter Flowchart

Examples:

– graphite

– pepper

– sugar (sucrose)

– paint

– soda

Element (Carbon)

heterogeneous mixture

compound

heterogeneous mixture

solution

B. Pure SubstancesB. Pure SubstancesElement

– Simplest form of matter that has a unique set of properties

– composed of identical atoms– EX: copper wire, aluminum foil

B. Pure SubstancesB. Pure Substances

CompoundCompound

– composed of 2 or more elements in a composed of 2 or more elements in a fixed ratio fixed ratio

2:1 - like H2:1 - like H22O or O or

1:1 like NaCl1:1 like NaCl

– properties differ from those of properties differ from those of individual elementsindividual elements

– EXEX: table salt (NaCl): table salt (NaCl)

B. Pure SubstancesB. 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 SubstancesB. Pure Substances For example…

Two different compounds, each has a definite composition.

C. MixturesC. Mixtures

Variable combination of 2 or more pure substances.

Heterogeneous Homogeneous

C. MixturesC. Mixtures

Homogeneous Mixture (aka Solution)– homogeneous– very small particles– no Tyndall effect

Tyndall Effect

particles don’t settleEX: rubbing alcohol

C. MixturesC. Mixtures

Heterogeneous Mixture

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

C. MixturesC. Mixtures

Heterogeneous MixtureSuspension

– heterogeneous– large particles– No true Tyndall effect– particles will settle– EX: fresh-squeezed

lemonade

C. MixturesC. Mixtures

Examples:

– mayonnaise

– muddy water

– fog

– saltwater

– Italian salad dressing

colloid

suspension

colloid

solution

suspension

Ch. 2: Matter & ChangesCh. 2: Matter & Changes

III. Properties & Changes

Extensive vs. Intensive

Physical vs. Chemical

A. Extensive vs. IntensiveA. 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. IntensiveA. Extensive vs. Intensive

Examples:

– boiling point

– volume

– mass

– density

– conductivity

Intensive

Extensive

Extensive

Intensive

intensive

B. Physical vs. ChemicalB. Physical vs. Chemical

Physical Property

– can be observed without changing the identity of the substance

Chemical Property

– describes the ability of a substance to undergo changes in identity

B. Physical vs. ChemicalB. Physical vs. Chemical

Examples:

– melting point

– flammable

– density

– magnetic

– tarnishes in air

Physical

Chemical

Physical

Physical

Chemical

B. Physical vs. ChemicalB. Physical vs. Chemical

Physical Change

– changes the form of a substance without changing its identity

– properties remain the same

Chemical Change

– changes the identity of a substance

– products have different properties

B. Physical vs. ChemicalB. Physical vs. Chemical

Signs of a Chemical Change

–change in color or odor

– formation of a gas

– formation of a precipitate (solid)

–change in energy (light or heat)

B. Physical vs. ChemicalB. Physical vs. Chemical

Examples:

– rusting iron

– dissolving in water

– burning a log

– melting ice

– grinding spices

chemical

physical

chemical

physical

physical

B. Physical vs. ChemicalB. Physical vs. Chemical

Law of Conservation of MassMass can not be created nor destroyed

*Mass of Reactants = Mass of Products