Chapter 2Chapter 2Matter and ChangeMatter and Change

Hingham High SchoolHingham High School

Mr. CluneMr. Clune

What is Matter?What is Matter?

MatterMatter is anything that takes up is anything that takes up space and has mass.space and has mass.

MassMass- - amount of material or amount of material or “stuff” in an object“stuff” in an object

Weight is due to gravity, and Weight is due to gravity, and changes from location to changes from location to location; mass is always location; mass is always constant.constant.

Mass or W

eightM

ass or Weight

Types of MatterTypes of Matter

SubstanceSubstance- a particular kind of - a particular kind of matter - pure; is uniform (all the matter - pure; is uniform (all the same) and has a definite same) and has a definite composition (examples are composition (examples are elements & compounds)elements & compounds)– water; gold; lemonade?water; gold; lemonade?

MixtureMixture-- more than one kind of more than one kind of matter; has a variable compositionmatter; has a variable composition

Substance or Mixture???Substance or Mixture???

PropertiesProperties

Words that describe matter (adjectives)Words that describe matter (adjectives)

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

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

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

PropertiesProperties

Words that describe matter (adjectives)Words that describe matter (adjectives)

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

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

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

Properties????Properties????

States of matterStates of matter

SolidSolid- matter that can not flow - matter that can not flow (definite shape) and has definite (definite shape) and has definite volume.volume.LiquidLiquid- definite volume but takes the - definite volume but takes the shape of its container (flows).shape of its container (flows).GasGas- a substance without definite - a substance without definite volume or shape and can flow.volume 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. (water vapor?)room temperature. (water vapor?)

States of matterStates of matter

States of MatterStates of Matter

Solid

Liquid

Gas

Definite Volume?

YES

YES

NO

Definite Shape?

YES

NO

NO

Temp. increase

Small Expans.

Small Expans.

Large Expans.

Com-pressible?

NO

NO

YES

Solid Liquid Gas

Melt Evaporate

CondenseFreeze

Physical ChangesPhysical ChangesA change that changes A change that changes appearances, without appearances, without changing the composition.changing the composition.

Ex. Boil, melt, cut, bend, split, Ex. Boil, melt, cut, bend, split, crackcrack

Boiled water is still water.Boiled water is still water.

Chemical ChangesChemical ChangesChemical changesChemical changes - a change - a change

where a new form of matter is where a new form of matter is formed.formed.

Ex. Rust, burn, decompose, Ex. Rust, burn, decompose, fermentferment

OO22 + Fe Fe + Fe Fe22OO33

MixturesMixtures

Physical blendPhysical blend of at least two of at least two substances; variable substances; variable compositioncompositionHeterogeneousHeterogeneous- mixture is not - mixture is not uniform in compositionuniform in compositionChocolate chip cookie, gravel, Chocolate chip cookie, gravel, soil.soil.

MixturesMixtures

HomogeneousHomogeneous- same - same composition throughout; called composition throughout; called ““solutionssolutions””Kool-aid, air, salt waterKool-aid, air, salt waterEvery part keeps it’s own Every part keeps it’s own properties.properties.

MixturesMixtures

HeterogeneousHeterogeneous HomogeneousHomogeneous

SolutionsSolutions

Homogeneous mixtureHomogeneous mixture

Mixed molecule by moleculeMixed molecule by molecule

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

SolutionsSolutions

Like all mixtures, they keep the Like all mixtures, they keep the properties of the components.properties of the components.

Some can be separated easily Some can be separated easily by physical means: rocks and by physical means: rocks and marbles, iron filings and sulfur marbles, iron filings and sulfur

Other methods: Other methods: distillationdistillation- - takes advantage of different takes advantage of different boiling pointsboiling points

DistillationDistillation

FiltrationFiltration

Water FiltrationWater Filtration

HomeworkHomework

WorksheetsWorksheetsSection 2-1Section 2-1

Section 2-2Section 2-2

Section 2.3Section 2.3Elements and CompoundsElements and Compounds

SubstancesSubstances

ElementsElements CompoundsCompounds

HgCu

H AuNaCl

H2O

CO 2

Elements Elements

ElementElement–A pure substance that A pure substance that cannot be made simpler by cannot be made simpler by known chemical meansknown chemical means

Examples: hydrogen, oxygen, Examples: hydrogen, oxygen, nitrogen, carbon, phosphorus, nitrogen, carbon, phosphorus, sodium, potassium and sodium, potassium and chlorinechlorine

Elements Elements

Each element is Each element is represented by a symbol represented by a symbol that usually consists of one that usually consists of one or two lettersor two letters

Hydrogen (H), Oxygen (O), Hydrogen (H), Oxygen (O), Carbon (C), Chlorine (Cl), Carbon (C), Chlorine (Cl), Sodium (Na)Sodium (Na)

CompoundsCompounds

Pure substances produced Pure substances produced from the chemical from the chemical combination of elementscombination of elements

Examples: water (HExamples: water (H22O) is a O) is a compound of hydrogen and compound of hydrogen and oxygen, sodium chloride (NaCl) oxygen, sodium chloride (NaCl) is a compound of sodium and is a compound of sodium and chlorine.chlorine.

CompoundsCompounds

–Has a fixed compositionHas a fixed composition–Has its own characteristic Has its own characteristic propertiesproperties

HH22 is a combustible gas, O is a combustible gas, O2 2 is is a gas helps burning but Ha gas helps burning but H22O is O is a liquid that is used to a liquid that is used to extinguish fire.extinguish fire.

Compound or MixtureCompound or Mixture

Compound Mixture

Made of one kind of material

Made of more thanone kind of material

Made by a chemical change

Made by a physical change

Definitecomposition

Variablecomposition

Which is it?Which is it?

Element

Compound

Mixture

Chemical Symbols & FormulasChemical Symbols & Formulas

Chemical Symbols & FormulasChemical Symbols & Formulas

Currently, there are 116 Currently, there are 116 elementselements

Each has a 1 or two letter Each has a 1 or two letter symbolsymbol

First letter always capitalized; First letter always capitalized; the second never; chemical the second never; chemical “shorthand”“shorthand”

Some from Latin or other Some from Latin or other languages; languages;

Chemical ReactionsChemical Reactions

HH220 H0 H22 + O + O22

YieldsYields

ReactantsReactants

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Chemical ReactionsChemical Reactions

When one or more When one or more substances are changed into substances are changed into new substances.new substances.

ReactantsReactants- stuff you start - stuff you start withwith

ProductsProducts- What you make- What you make

Chemical ReactionsChemical Reactions

Ability to undergo chemical Ability to undergo chemical reaction is called a reaction is called a chemical chemical propertyproperty

Products have NEW Products have NEW PROPERTIESPROPERTIES

Arrow from reactants to Arrow from reactants to productsproducts

IndicationsIndications of a chemical reaction: of a chemical reaction:

EnergyEnergy absorbed or released absorbed or released (temperature changes hotter (temperature changes hotter or colder)or colder)

ColorColor change change

GasGas production (bubbling, production (bubbling, fizzing, or odor change)fizzing, or odor change)

IndicationsIndications of a chemical reaction: of a chemical reaction:

Formation of aFormation of a precipitateprecipitate- - a solid that separates from a solid that separates from solution (won’t dissolve)solution (won’t dissolve)

IrreversibilityIrreversibility- not easily - not easily reversedreversed

Law of Conservation of Mass Law of Conservation of Mass

Mass can not be created or Mass can not be created or destroyed in ordinary (not destroyed in ordinary (not nuclear) chemical reactions or nuclear) chemical reactions or physical changephysical change

Law of Conservation of Mass Law of Conservation of Mass

All the mass can be All the mass can be accounted for.accounted for.–Burning of wood results in Burning of wood results in products that appear to products that appear to have less mass as ash; have less mass as ash; where is the rest?where is the rest?

Law of Conservation of MassLaw of Conservation of Mass

HH220 H0 H22 + O + O222222

ReactantsReactants

}

ProductsProducts}

10g 10g

HomeworkHomework

Worksheets 2.3 & 2.4Worksheets 2.3 & 2.4Due: 9/20/05 Due: 9/20/05 Test: 9/21/05Test: 9/21/05