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Chapter 2Chapter 2Matter and ChangeMatter and Change

Charles Page High SchoolCharles Page High School

Dr. Stephen L. CottonDr. Stephen L. Cotton

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Section 2.1Section 2.1MatterMatter

OBJECTIVES:OBJECTIVES:

–Identify the characteristics of Identify the characteristics of matter and substances.matter and substances.

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Section 2.1Section 2.1MatterMatter

OBJECTIVES:OBJECTIVES:

–Differentiate among the three Differentiate among the three states of matter.states of matter.

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Section 2.1Section 2.1MatterMatter

OBJECTIVES:OBJECTIVES:

–Define physical property, and list Define physical property, and list several common physical several common physical properties of substances.properties of substances.

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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 “stuff” in amount of material or “stuff” in

an objectan object Weight is due to gravity, and Weight is due to gravity, and

changes from location to location; changes from location to location; mass is always constant.mass is always constant.

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Types of MatterTypes of Matter SubstanceSubstance- a particular kind of matter - a particular kind of matter

- pure; is uniform (all the same) and - pure; is uniform (all the same) and has a definite composition (examples has a definite composition (examples are elements & compounds)are 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

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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.

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

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

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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

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Solid Liquid Gas

Melt Evaporate

CondenseFreeze

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Physical ChangesPhysical Changes A change that changes appearances, A change that changes appearances,

without changing the composition.without changing the composition. Ex. Boil, melt, cut, bend, split, crackEx. Boil, melt, cut, bend, split, crack Boiled water is still water.Boiled water is still water. Chemical changesChemical changes - a change where - a change where

a new form of matter is formed.a new form of matter is formed. Ex. Rust, burn, decompose, fermentEx. Rust, burn, decompose, ferment

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Section 2.2Section 2.2MixturesMixtures

OBJECTIVES:OBJECTIVES:

–Categorize a sample of matter as Categorize a sample of matter as a substance or a mixture.a substance or a mixture.

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Section 2.2Section 2.2MixturesMixtures

OBJECTIVES:OBJECTIVES:

–Distinguish between homogeneous Distinguish between homogeneous and heterogeneous samples of and heterogeneous samples of matter.matter.

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MixturesMixtures Physical blendPhysical blend of at least two of at least two

substances; variable compositionsubstances; variable composition HeterogeneousHeterogeneous- mixture is not uniform in - mixture is not uniform in

compositioncomposition Chocolate chip cookie, gravel, soil.Chocolate chip cookie, gravel, soil. HomogeneousHomogeneous- same composition - same composition

throughout; called “throughout; 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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SolutionsSolutions Homogeneous mixtureHomogeneous mixture Mixed molecule by moleculeMixed molecule by molecule Can occur between any state of Can occur between any state of

mattermatter–Table 2.3, page 33Table 2.3, page 33–gas in gas; liquid in gas; gas in gas in gas; liquid in gas; gas in

liquid; solid in liquid; solid in solid liquid; solid in liquid; solid in solid (alloys), etc.(alloys), etc.

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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 by Some can be separated easily by

physical means: rocks and marbles, physical means: rocks and marbles, iron filings and sulfur iron filings and sulfur

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

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Section 2.3Section 2.3Elements and CompoundsElements and Compounds

OBJECTIVES:OBJECTIVES:

–Explain the differences between Explain the differences between an element and a compound.an element and a compound.

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Section 2.3Section 2.3Elements and CompoundsElements and Compounds

OBJECTIVES:OBJECTIVES:

–Identify the chemical symbols of Identify the chemical symbols of common elements, and name common elements, and name common elements given their common elements given their symbols.symbols.

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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 are substances that can be

broken down broken 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 physical blend!)combined (not physical blend!)

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Compound or MixtureCompound 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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Chemical Symbols & FormulasChemical Symbols & Formulas Currently, there are 115 elementsCurrently, there are 115 elements Each has a 1 or two letter Each has a 1 or two letter symbolsymbol First letter always capitalized; the First letter always capitalized; the

second never; chemical “shorthand”second never; chemical “shorthand” Don’t need to memorize all of them; Don’t need to memorize all of them;

know Table A.3 inside back coverknow Table A.3 inside back cover Some from Latin or other languages; Some from Latin or other languages;

note Table 2.4, page 40note Table 2.4, page 40

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Section 2.4Section 2.4Chemical ReactionsChemical Reactions

OBJECTIVES:OBJECTIVES:

–Differentiate between physical Differentiate between physical and chemical changes in matter.and chemical changes in matter.

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Section 2.4Section 2.4Chemical ReactionsChemical Reactions

OBJECTIVES:OBJECTIVES:

–Apply the Law of Conservation of Apply the Law of Conservation of Mass.Mass.

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Chemical ReactionsChemical Reactions When one or more substances are When one or more substances are

changed into new substances.changed into new substances. ReactantsReactants- stuff you start with- stuff you start with ProductsProducts- What you make- What you make ability to undergo chemical reaction is ability to undergo chemical reaction is

called a called a chemical propertychemical property products have NEW PROPERTIESproducts have NEW PROPERTIES Arrow from reactants to productsArrow from reactants to products

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IndicationsIndications of a chemical reaction: of a chemical reaction: EnergyEnergy absorbed or released absorbed or released

(temperature changes hotter or colder)(temperature changes hotter or colder) ColorColor change change GasGas production (bubbling, fizzing, or production (bubbling, fizzing, or

odor change)odor change) formation of aformation of a precipitateprecipitate- a solid that - a solid that

separates from solution (won’t dissolve)separates from solution (won’t dissolve) IrreversibilityIrreversibility- not easily reversed- not easily reversed

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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 nuclear) destroyed in ordinary (not nuclear) chemical reactions or physical chemical reactions or physical changechange

All the mass can be accounted for.All the mass can be accounted for.

–Burning of wood results in Burning of wood results in products that appear to have less products that appear to have less mass as ash; where is the rest?mass as ash; where is the rest?