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Properties ofProperties ofMatterMatter

Central SchoolCentral School8th Grade8th GradeMr. SitzMr. Sitz

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MatterMatter MatterMatter is anything that: is anything that:

– has masshas mass– takes up spacetakes up space

MassMass = a measure of the amount of “stuff” (or = a measure of the amount of “stuff” (or material) the object contains. *don’t confuse this material) the object contains. *don’t confuse this with weight, a measure of gravitywith weight, a measure of gravity

VolumeVolume = a measure of the space occupied by = a measure of the space occupied by the objectthe object

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Describing MatterDescribing Matter Properties used to describe matter can be Properties used to describe matter can be

classified as:classified as:1)1) ExtensiveExtensive – depends on the – depends on the amountamount of of

matter in the samplematter in the sample- Mass, volume, calories are examplesMass, volume, calories are examples

2)2) IntensiveIntensive – depends on the – depends on the typetype of matter, of matter, not the amount presentnot the amount present

- Hardness, Density, Boiling Point- Hardness, Density, Boiling Point

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Properties are…Properties are… Words that describe matter (adjectives)Words that describe matter (adjectives)

Physical PropertiesPhysical Properties- a property that can be - a property that can be observed and measured without changing the observed and measured without changing the material’s composition.material’s composition.

Examples- color, hardness, m.p., b.p.Examples- color, hardness, m.p., b.p.

Chemical PropertiesChemical Properties- a property that can only - a property that can only be observed by changing the composition of the be observed by changing the composition of the material. material.

Examples- ability to burn, decompose, Examples- ability to burn, decompose, ferment, react with, etc. ferment, react with, etc.

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States of matterStates of matter1)1) SolidSolid- matter that can not flow (definite - matter that can not flow (definite

shape) and has definite volume.shape) and has definite volume.

2)2) LiquidLiquid- definite volume but takes the - definite volume but takes the shape of its container (flows).shape of its container (flows).

3)3) GasGas- a substance without definite volume - a substance without definite volume or shape and can flow.or shape and can flow.

– VaporVapor- a substance that is currently a - a substance that is currently a gas, but normally is a liquid or solid at gas, but normally is a liquid or solid at room temperature. (Which is correct: room temperature. (Which is correct: water gas, or water vapor?)water gas, or water vapor?)

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States of MatterStates of Matter

Solid

Liquid

Gas

Definite Volume?

YES

YES

NO

Definite Shape?

YES

NO

NO

Result of a TemperatureIncrease?

Small Expanse

Small Expanse

Large Expanse

Will it Compress?

NO

NO

YES

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44thth state: state: PlasmaPlasma - formed at high - formed at high temperatures; ionized phase of matter as temperatures; ionized phase of matter as

found in the sun.found in the sun.

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Three Main PhasesThree Main Phases

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Solid Liquid Gas

Melt Evaporate

CondenseFreeze

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Copper Phases - SolidCopper Phases - Solid

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Copper Phases - LiquidCopper Phases - Liquid

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Copper Phases – Vapor (gas)Copper Phases – Vapor (gas)

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Physical vs. Chemical ChangePhysical vs. Chemical Change Physical changePhysical change will change the appearance, will change the appearance,

without changing the composition of the material.without changing the composition of the material.– Boil, melt, cut, bend, split, crackBoil, melt, cut, bend, split, crack– Is boiled water still water?Is boiled water still water?

Can be Can be reversiblereversible, or , or irreversibleirreversible

Chemical changeChemical change - a change where a new form - a change where a new form of matter is formed.of matter is formed.– Rust, burn, decompose, fermentRust, burn, decompose, ferment

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MixturesMixtures Mixtures are a physical blendMixtures are a physical blend of at least two of at least two

substances; have variable composition. They substances; have variable composition. They can be either:can be either:

1)1) Heterogeneous Heterogeneous – the mixture is not uniform in – the mixture is not uniform in compositioncomposition

• Chocolate chip cookie, gravel, soil.Chocolate chip cookie, gravel, soil.

2)2) Homogeneous Homogeneous - same composition throughout; - same composition throughout; called “called “solutionssolutions””

• Kool-aid, air, salt waterKool-aid, air, salt water Every part keeps it’s own properties.Every part keeps it’s own properties.

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Solutions are homogeneous mixturesSolutions are homogeneous mixtures Mixed molecule by molecule, thus too small to Mixed molecule by molecule, thus too small to

see the different partssee the different parts

Can occur between any state of matter: gas in Can occur between any state of matter: gas in gas; liquid in gas; gas in liquid; solid in liquid; gas; liquid in gas; gas in liquid; solid in liquid; solid in solid (alloys), etc.solid in solid (alloys), etc.

Thus, based on the distribution of their Thus, based on the distribution of their components, mixtures are called components, mixtures are called homogeneoushomogeneous or or heterogeneousheterogeneous..

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Phase?Phase? The term “phase” is used to describe any part of The term “phase” is used to describe any part of

a sample with uniform composition of a sample with uniform composition of properties.properties.

A homogeneous mixture consists of a A homogeneous mixture consists of a singlesingle phasephase

A heterogeneous mixture consists of A heterogeneous mixture consists of two or two or moremore phases. phases.

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Separating MixturesSeparating Mixtures Some can be separated easily by physical Some can be separated easily by physical

means: rocks and marbles, iron filings and sulfur means: rocks and marbles, iron filings and sulfur (use magnet) (use magnet)

Differences in physical properties can be used to Differences in physical properties can be used to separate mixtures.separate mixtures.

FiltrationFiltration - separates a solid from the liquid in a - separates a solid from the liquid in a heterogeneous mixture (by size)heterogeneous mixture (by size)

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Separation of a MixtureSeparation of a MixtureComponents of dyes such as ink may be separated by paper chromatography.

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Separation of a MixtureSeparation of a Mixture

Distillation: takes advantage of different boiling points.

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SubstancesSubstances ElementsElements- simplest kind of matter- simplest kind of matter

– cannot be broken down any simplercannot be broken down any simpler– all all oneone kind of atom. kind of atom.

CompoundsCompounds are substances that can be broken are substances that can be broken down down onlyonly by chemical methods by chemical methods– when broken down, the pieces have when broken down, the pieces have

completely different properties than the completely different properties than the original compound.original compound.

– made of made of two or moretwo or more atoms, chemically atoms, chemically combined (not just a physical blend!) combined (not just a physical blend!)

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Compound or Mixture?Compound or Mixture?

Compound Mixture

Made of one kindof material

Made of more thanone kind of material

Made by a chemical change

Made by a physical change

Definitecomposition

Variablecomposition

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Which is it?Which is it?

ElementCompoundMixture

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Elements vs. CompoundsElements vs. Compounds Compounds Compounds cancan be broken down into simpler be broken down into simpler

substances by chemical means, but substances by chemical means, but elements elements cannotcannot..

A “A “chemical changechemical change” is a change that produces ” is a change that produces matter with a matter with a different compositiondifferent composition than the than the original matter.original matter.

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Chemical ChangeChemical ChangeA change in which one or more substances are converted into different substances.

Heat and light are often evidence of a chemical change.

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Properties of CompoundsProperties of Compounds Quite different properties than their component Quite different properties than their component

elements.elements.

Due to a CHEMICAL CHANGE, the resulting Due to a CHEMICAL CHANGE, the resulting compound has new and different properties:compound has new and different properties:• Table sugar – carbon, hydrogen, oxygenTable sugar – carbon, hydrogen, oxygen• Sodium chloride – sodium, chlorineSodium chloride – sodium, chlorine• Water – hydrogen, oxygenWater – hydrogen, oxygen

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Classification of MatterClassification of Matter

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Symbols & FormulasSymbols & Formulas Currently, there are Currently, there are 117117 elements elements Elements have a 1 or two letter Elements have a 1 or two letter symbolsymbol, and , and

compounds have a compounds have a formulaformula.. An element’s first letter always capitalized; if An element’s first letter always capitalized; if

there is a second letter, it is written lowercase: there is a second letter, it is written lowercase: B, Ba, C, Ca, H, HeB, Ba, C, Ca, H, He

Some names come from Latin or other Some names come from Latin or other languages.languages.

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Chemical ChangesChemical Changes The ability of a substance to undergo a specific The ability of a substance to undergo a specific

chemical change is called a chemical change is called a chemical propertychemical property..• iron plus oxygen forms rust, so the ability to iron plus oxygen forms rust, so the ability to

rust is a chemical property of ironrust is a chemical property of iron

During a chemical change (also called chemical During a chemical change (also called chemical reaction), the composition of matter always reaction), the composition of matter always changes. changes.

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Chemical Reactions are…Chemical Reactions are… When one or more substances are changed into When one or more substances are changed into

new substances.new substances. ReactantsReactants- the stuff you start with- the stuff you start with ProductsProducts- what you make- what you make The products will have NEW PROPERTIES The products will have NEW PROPERTIES

different from the reactants you started withdifferent from the reactants you started with Arrow points from the reactants Arrow points from the reactants toto the new the new

productsproducts

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Recognizing Chemical ChangesRecognizing Chemical Changes1)1) EnergyEnergy is absorbed or released (temperature is absorbed or released (temperature

changes hotter or colder)changes hotter or colder)

2)2) ColorColor changes changes

3)3) GasGas production (bubbling, fizzing, or odor production (bubbling, fizzing, or odor change; smoke)change; smoke)

4)4) formation of aformation of a precipitateprecipitate - a solid that - a solid that separates from solution (won’t dissolve)separates from solution (won’t dissolve)

5)5) IrreversibilityIrreversibility - not easily reversed But, there - not easily reversed But, there are examples of these that are not chemical – are examples of these that are not chemical – boiling water bubbles, etc.boiling water bubbles, etc.

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Conservation of Mass Conservation of Mass During any chemical reaction, the mass of the During any chemical reaction, the mass of the

products is always equal to the mass of the products is always equal to the mass of the reactants.reactants.

All the massAll the mass can be accounted for: can be accounted for:– Burning of wood results in products that Burning of wood results in products that

appear to have less mass as ashes; where is appear to have less mass as ashes; where is the rest?the rest?

Law of conservation of massLaw of conservation of mass

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reactants = product

43.43 g Original mass = 43.43 g Final mass