Matter and ChangeMatter and Change

MatterMatter

Anything that has mass and takes up Anything that has mass and takes up spacespace

Mass – measures the amount of matterMass – measures the amount of matter

2 Kinds of Matter: Substances and 2 Kinds of Matter: Substances and MixturesMixtures

0.00043kg0.00043kg 5000 - 6500 kg5000 - 6500 kg

Pure SubstancesPure Substances

Uniform and definite compositionUniform and definite composition

Only contain ONE kind of matterOnly contain ONE kind of matter

There are two kinds of substances.There are two kinds of substances.

Pure SubstancesPure Substances

Examples: Examples: – Pure waterPure water– table sugartable sugar– baking sodabaking soda

Non – Examples:Non – Examples:– LemonadeLemonade– Chocolate chip cookie Chocolate chip cookie

doughdough

Pure Pure SubstancesSubstances

ElementElement– simplest form of mattersimplest form of matter– Made of one kind of atomMade of one kind of atom– Building blocks for all other substancesBuilding blocks for all other substances– Represented by a Represented by a chemical symbolchemical symbol– Examples: lithium, hydrogen, chlorine, carbon, Examples: lithium, hydrogen, chlorine, carbon,

aluminum, copper… look at the periodic table!aluminum, copper… look at the periodic table!

Chemical SymbolsChemical Symbols

Representation of each elementRepresentation of each elementFirst letter capitalized, second letter lower First letter capitalized, second letter lower casecaseUsually resembles the nameUsually resembles the nameSome symbols are based on the Latin or Some symbols are based on the Latin or Greek name and do not resemble the Greek name and do not resemble the English name English name – Example: ferrum is Latin for iron (Fe)Example: ferrum is Latin for iron (Fe)

Look at the periodic table!Look at the periodic table!

Pure SubstancesPure Substances

CompoundCompound–Matter that can be broken down Matter that can be broken down

into simpler forms by chemical into simpler forms by chemical reactionsreactions

–Examples: sugar (C6H12O6), Examples: sugar (C6H12O6), salt (NaCl), water (H2O)salt (NaCl), water (H2O)

MixturesMixtures

Physical blends of two or more substancesPhysical blends of two or more substances

Composition may varyComposition may vary

PhasePhase

Any part of a system with uniform Any part of a system with uniform composition and propertiescomposition and properties

Example: oil and vinegar saladExample: oil and vinegar salad

dressing, car oil on a water puddledressing, car oil on a water puddle

Heterogeneous MixtureHeterogeneous Mixture

Not uniform in compositionNot uniform in composition

Can have more than one phaseCan have more than one phase

Examples: salad or a bag of M&MsExamples: salad or a bag of M&Ms

Heterogeneous Mixtures – Heterogeneous Mixtures – Special Case 1Special Case 1

ColloidColloid– medium-sized particlesmedium-sized particles– Show the Tyndall effectShow the Tyndall effect– particles don’t settleparticles don’t settle– EXEX::

MilkMilk

MarshmallowsMarshmallows

SnotSnot

JellyJelly

ButterButter

Heterogeneous Mixtures –Heterogeneous Mixtures –Special Case 2Special Case 2

SuspensionSuspension– large particleslarge particles– Show greater Tyndall Show greater Tyndall

effecteffect– particles settle eventuallyparticles settle eventually– EXEX:: fresh-squeezed fresh-squeezed

lemonadelemonade

Tyndall EffectTyndall Effect

Homogeneous Mixture (solution)Homogeneous Mixture (solution)

Uniform in Uniform in compositioncomposition

Only one phaseOnly one phase

Examples: Examples: – Salt water (NaCl in Salt water (NaCl in

solution with Hsolution with H22O)O)– Sterling silver (alloy of Sterling silver (alloy of

Cu and Ag)Cu and Ag)– Vinegar (acetic acid in Vinegar (acetic acid in

water)water)

SolutionsSolutions

Homogeneous Homogeneous mixturesmixtures

May be liquid, solid or May be liquid, solid or gasgas

No Tyndall effectNo Tyndall effect

Define…Define…

Examples:Examples:

– mayonnaisemayonnaise

– muddy watermuddy water

– fogfog

– saltwatersaltwater

– Italian salad Italian salad dressingdressing

colloidcolloid

suspensionsuspension

colloidcolloid

solutionsolution

suspensionsuspension

Separating MixturesSeparating Mixtures

Simple physical methodsSimple physical methods– Use a fork to pick out the tomatoes from your Use a fork to pick out the tomatoes from your

saladsalad– Classify M&M’s by colorClassify M&M’s by color

Use knowledge of physical propertiesUse knowledge of physical properties– Separate iron from sulfur using a magnetSeparate iron from sulfur using a magnet– Separate water from salt by boiling the Separate water from salt by boiling the

solutionsolution

DistillationDistillation

Process used to separate Process used to separate liquids from dissolved liquids from dissolved solids in homogeneous solids in homogeneous mixturesmixtures

1.1. Solution is heated to boiling Solution is heated to boiling pointpoint

2.Vapor forms; dissolved solids 2.Vapor forms; dissolved solids are left behindare left behind

3.Vapor is condensed to liquid3.Vapor is condensed to liquid

4.Collected liquid is pure except 4.Collected liquid is pure except for dissolved gasesfor dissolved gases

Physical PropertyPhysical Property

A quality or condition of a substance that can be A quality or condition of a substance that can be observed or measured observed or measured without changingwithout changing the the substance’s compositionsubstance’s composition

ExamplesExamples– ColorColor– SolubilitySolubility– DensityDensity– Melting or boiling pointMelting or boiling point– OdorOdor– HardnessHardness

Using Physical PropertiesUsing Physical Properties

Mystery substance…Mystery substance…– OdorlessOdorless– Freezes at 0 °CFreezes at 0 °C– Boils at 100 °CBoils at 100 °C– Has a density of 1 g/ cm³Has a density of 1 g/ cm³– ClearClear

What is the mystery substance?What is the mystery substance?

WATER!

Chemical propertyChemical property

Describes ability to undergo chemical Describes ability to undergo chemical changechange

Observed only when a substance Observed only when a substance undergoes chemical changeundergoes chemical change

Examples:Examples:– DecomposibleDecomposible– RustRust– CombustibleCombustible

Physical or Chemical Property?Physical or Chemical Property?

ColorColor

RustyRusty

FlammabilityFlammability

Melting pointMelting point

Boiling pointBoiling point

FermentabilityFermentability

MassMass

DensityDensity

PhysicalPhysical

ChemicalChemical

ChemicalChemical

PhysicalPhysical

PhysicalPhysical

ChemicalChemical

PhysicalPhysical

PhysicalPhysical

States of MatterStates of Matter

Physical states are physical properties.Physical states are physical properties.

SOLIDS LIQUIDS GASES

SolidsSolids

Definite volumeDefinite volume

Definite shapeDefinite shape

Particles are packed Particles are packed

tightly and vibratetightly and vibrate

Nearly IncompressibleNearly Incompressible

Expand only slightly Expand only slightly

when heatedwhen heated

iron

ice

gold

LiquidsLiquids

Definite volumeDefinite volume

Take the shape of Take the shape of

their containerstheir containers

Flow – particles touch Flow – particles touch

but not rigidly packedbut not rigidly packed

Nearly incompressibleNearly incompressible

Expand when heatedExpand when heated

Hg - mercury

H2O - water

GasesGases

No definite volumeNo definite volume

Take the shape of their Take the shape of their

containerscontainers

Particle are spaced far Particle are spaced far

apartapart

Very compressibleVery compressible

Expand when heatedExpand when heated

Examples: oxygen, Examples: oxygen,

helium, carbon dioxidehelium, carbon dioxide

Gas or Solid?Gas or Solid?

GAS SOLID

Gases vs. VaporGases vs. Vapor

Gas – exists in the gaseous state at room Gas – exists in the gaseous state at room temperaturetemperature

Vapor – gaseous state of a substance that Vapor – gaseous state of a substance that is generally a liquid or a solid at room is generally a liquid or a solid at room temperaturetemperature

Steam is water vaporSteam is water vapor

FluidsFluids

A substance that is capable of flowing and A substance that is capable of flowing and changing its shape at a steady ratechanging its shape at a steady rate

Which states of matter do you think are Which states of matter do you think are fluids?fluids?

Gases and Liquids

Properties of FluidsProperties of Fluids

Density – expresses the Density – expresses the relationship between relationship between mass and volumemass and volume

Viscosity – how much the Viscosity – how much the fluid resists flowingfluid resists flowing– Water has a low viscosityWater has a low viscosity– Ketchup has a high Ketchup has a high

viscosityviscosity

Buoyancy – the property Buoyancy – the property to float or rise in a fluidto float or rise in a fluid

The milkshake is VISCOUS

The gold bar is DENSE

The beach ball is BUOYANT

Physical ChangesPhysical Changes

Matter is altered without altering the Matter is altered without altering the chemical composition of the materialchemical composition of the material

Examples: cutting, grinding, bending, Examples: cutting, grinding, bending, freezing, melting, boiling dissolving, freezing, melting, boiling dissolving, condensing, crushing, breakingcondensing, crushing, breaking

Chemical ChangesChemical Changes

The chemical composition of a substance The chemical composition of a substance is alteredis altered

Examples: rusting, burning, rotting, Examples: rusting, burning, rotting, exploding, fermenting, decomposing, exploding, fermenting, decomposing, corrodingcorroding

Physical or Chemical?Physical or Chemical?

Physical changes do not change the Physical changes do not change the chemical composition; chemical reactions chemical composition; chemical reactions do.do.

Physical changes are usually easily Physical changes are usually easily reversed; chemical reactions are not as reversed; chemical reactions are not as easily reversedeasily reversed– Freezing water and melting iceFreezing water and melting ice– Burning a piece of paperBurning a piece of paper

What is the difference here?What is the difference here?

Physical Changes: changes Physical Changes: changes between states of matterbetween states of matter

Melting – solid to liquidMelting – solid to liquid

Freezing – liquid to solidFreezing – liquid to solid

Vaporization – liquid to gas (evaporation)Vaporization – liquid to gas (evaporation)

Condensation – gas to liquidCondensation – gas to liquid

Sublimation – solid straight to gasSublimation – solid straight to gas

Crystallization – gas to solidCrystallization – gas to solid

Chemical Changes:Chemical Changes:Chemical ReactionsChemical Reactions

One or more REACTANTS change into One or more REACTANTS change into new PRODUCTSnew PRODUCTS

There is no chemical reaction in a physical There is no chemical reaction in a physical change.change.

Chemical FormulasChemical Formulas

““recipe” for a substance or reactionrecipe” for a substance or reaction

Use symbols when writing formulasUse symbols when writing formulas

Examples:Examples:– Water: HWater: H22OO– Photosynthesis: Photosynthesis:

6H6H22O + 6COO + 6CO22 → C → C66HH1212OO66 + 6O + 6O22

REACTANTS PRODUCTS

Writing Reaction FormulasWriting Reaction Formulas

Reactants – left of the arrowReactants – left of the arrow

Arrow – means “changes to” or “produces”Arrow – means “changes to” or “produces”

Products – right of the arrowProducts – right of the arrow

Photosynthesis: Photosynthesis: 6H6H22O + 6COO + 6CO22 → C → C66HH1212OO66 + 6O + 6O22

REACTANTSWater and carbon dioxide

PRODUCTSSucrose and oxygen

Chemical Change: OxidationChemical Change: Oxidation

Rust is the product of an oxidation reaction!Rust is the product of an oxidation reaction!

An oxidation reaction always involves gaining An oxidation reaction always involves gaining oxygen, and losing electrons.oxygen, and losing electrons.

Anytime you have an oxidation reaction, you Anytime you have an oxidation reaction, you also have a reduction reaction. also have a reduction reaction.

Reduction is losing oxygen and gaining Reduction is losing oxygen and gaining electrons.electrons.

Chemical Change: OxidationChemical Change: Oxidation

““LEOLEO the lion goes the lion goes GERGER””– LLosing osing EElectrons lectrons OOxidationxidation– GGaining aining EElectrons lectrons RReductioneduction

ExamplesExamples– Burning: CHBurning: CH44 + O + O22 CO CO22 + H + H2200– Rusting: 4Fe + 3ORusting: 4Fe + 3O22 = 2Fe = 2Fe22OO33

Electroplating uses a redox reaction to coat one Electroplating uses a redox reaction to coat one metal with another. This protects the item metal with another. This protects the item against corrosion.against corrosion.

Digestion – Physical and Chemical Digestion – Physical and Chemical ChangesChanges

The digestive system includes the The digestive system includes the digestive tract and its accessory organs digestive tract and its accessory organs Food is broken down, bit by bit, until the Food is broken down, bit by bit, until the molecules are small enough to be molecules are small enough to be absorbed and the waste products are absorbed and the waste products are eliminated.eliminated. Is chewing a physical or chemical change?Is chewing a physical or chemical change?Does stomach acid cause a physical or Does stomach acid cause a physical or chemical change?chemical change?

The Rock Cycle: Chemical and The Rock Cycle: Chemical and Physical ChangesPhysical Changes

The recycling of the Earth's outer layers - rocks are The recycling of the Earth's outer layers - rocks are continually being formed, destroyed, and re-formed in an continually being formed, destroyed, and re-formed in an endless cycle of change that takes millions of years. endless cycle of change that takes millions of years.

Physical Changes: Physical Changes: – surface weathering and erosionsurface weathering and erosion– the compaction and cementation of sediments into sedimentary the compaction and cementation of sediments into sedimentary

rockrock

Chemical Changes:Chemical Changes:– formation of igneous rock from magma (molten rock)formation of igneous rock from magma (molten rock)

Metamorphism - chemical and physical changes brought Metamorphism - chemical and physical changes brought about by heat and pressure, producing metamorphic about by heat and pressure, producing metamorphic rockrock

Conservation of MassConservation of Mass

During physical and chemical changes, matter During physical and chemical changes, matter is…is…– NOT createdNOT created– NOT destroyedNOT destroyed

It simply changes from one form to anotherIt simply changes from one form to another

Similar to the law of conservation of energySimilar to the law of conservation of energy

Conservation: Physical ChangeConservation: Physical Change

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Conservation: Chemical ChangeConservation: Chemical Change

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