Matter Chapter 2 Modified from Holt, Rinehart, and Winston presentation for textbook Science Spectrum: Physical Science

MatterMatter

Chapter 2Chapter 2Modified from Holt, Rinehart, and Winston presentation for textbook Modified from Holt, Rinehart, and Winston presentation for textbook

Science Spectrum: Physical ScienceScience Spectrum: Physical Science

Section 1 What Is Matter?

ObjectivesObjectives ExplainExplain the relationship between matter, atoms, and the relationship between matter, atoms, and

elements.elements.

DistinguishDistinguish between elements and compounds. between elements and compounds.

DescribeDescribe molecules, and explain how they are molecules, and explain how they are formed.formed.

InterpretInterpret and write some common chemical and write some common chemical formulas.formulas.

CategorizeCategorize materials as pure substances or mixtures. materials as pure substances or mixtures.

Chapter 2

Composition of MatterComposition of Matter Matter Matter is anything that has mass and takes up spaceis anything that has mass and takes up space

Know these definitions from your study guide!Know these definitions from your study guide! Chemistry Chemistry is the scientific study of the composition, is the scientific study of the composition,

structure, and properties of matter and the changes structure, and properties of matter and the changes that matter undergoesthat matter undergoes..

Element Element a substance that cannot be separated or a substance that cannot be separated or broken down into simpler substances by chemical broken down into simpler substances by chemical meansmeans

Atom Atom the smallest unit of an element that maintains the smallest unit of an element that maintains the properties of that elementthe properties of that element

Section 1 What Is Matter?Chapter 2

Elements in the Human BodyElements in the Human Body


MatterMatter


AtomAtom


ElementElement


Composition of Matter, Composition of Matter, continuedcontinued

Compound Compound a substance made of atoms of two a substance made of atoms of two or more different elements that are chemically or more different elements that are chemically combinedcombined


CompoundsCompounds



Compounds have unique properties.Compounds have unique properties.

• Every compound is different from the elements it Every compound is different from the elements it contains.contains.

When elements combine to form a specific When elements combine to form a specific compound, they always combine in the same compound, they always combine in the same proportions.proportions.



Molecules Molecules are the smallest unit of a substance are the smallest unit of a substance that keeps all of the physical and chemical that keeps all of the physical and chemical properties of that substanceproperties of that substance

A molecule acts as a single unit.A molecule acts as a single unit.

• Atoms can join together to make millions of Atoms can join together to make millions of molecules.molecules.


MoleculeMolecule



Chemical formula Chemical formula a combination of chemical a combination of chemical symbols and numbers to represent a substance.symbols and numbers to represent a substance.

Chemical formulas represent compounds and Chemical formulas represent compounds and molecules.molecules.

• A chemical formula shows how many atoms of A chemical formula shows how many atoms of each element are in a unit of a substance.each element are in a unit of a substance.


Chemical FormulaChemical Formula


Pure Substances and MixturesPure Substances and Mixtures Mixtures are formed by mixing pure Mixtures are formed by mixing pure

substances.substances.

Pure substance Pure substance a sample of matter, either a a sample of matter, either a single element or a single compound, that has single element or a single compound, that has definite chemical and physical propertiesdefinite chemical and physical properties

Mixture Mixture a combination of two or more a combination of two or more substances that are not chemically combinedsubstances that are not chemically combined


Pure Substances and Mixtures, Pure Substances and Mixtures, continuedcontinued

Mixtures are classified by how thoroughly the substances mix.Mixtures are classified by how thoroughly the substances mix.

Heterogeneous mixture Heterogeneous mixture substances aren’t mixed uniformly substances aren’t mixed uniformly and are not evenly distributedand are not evenly distributed

Homogeneous mixture Homogeneous mixture substances are evenly distributed, and substances are evenly distributed, and the mixture is the same throughoutthe mixture is the same throughout

Miscible Miscible substances that can be mixedsubstances that can be mixed

Immiscible Immiscible substances that cannot be mixedsubstances that cannot be mixed


Comparing Miscible and Comparing Miscible and Immiscible LiquidsImmiscible Liquids


Pure Substances and Mixtures, Pure Substances and Mixtures, continuedcontinued

Gases can mix with gases.Gases can mix with gases.• Air is a mixture of gases.Air is a mixture of gases.

Gases can mix with liquids.Gases can mix with liquids.

• Examples of gases mixed with liquids include Examples of gases mixed with liquids include • carbonated drinks carbonated drinks • oxygen dissolved in water oxygen dissolved in water • foamfoam


ObjectivesObjectives

DistinguishDistinguish between the physical and chemical between the physical and chemical properties of matter, and give examples of each.properties of matter, and give examples of each.

PerformPerform calculations involving density. calculations involving density.

ExplainExplain how materials are suited for different uses how materials are suited for different uses based on their physical and chemical properties, and based on their physical and chemical properties, and give examples.give examples.

DescribeDescribe characteristic properties, and give characteristic properties, and give examples.examples.

Section 2 Properties of MatterChapter 2

Physical PropertiesPhysical Properties Physical properties describe matter.Physical properties describe matter.

• Some examples of physical properties include shape, color, Some examples of physical properties include shape, color, size, mass, volume, density, melting point and boiling point.size, mass, volume, density, melting point and boiling point.

Melting point Melting point the temperature and pressure at which a the temperature and pressure at which a solid becomes a liquidsolid becomes a liquid

Boiling point Boiling point the temperature and pressure at which a the temperature and pressure at which a liquid becomes a gasliquid becomes a gas

State State the physical form in which a substance exists, the physical form in which a substance exists, such as solid, liquid, or gassuch as solid, liquid, or gas


Three States of WaterThree States of Water


Solid, Liquid and GasSolid, Liquid and Gas


Physical Properties, Physical Properties, continuedcontinued Density Density the ratio of the mass of a substance to the the ratio of the mass of a substance to the

volume of a substancevolume of a substance

• Density is a physical property and is a measurement Density is a physical property and is a measurement of how much matter is contained in a certain volume of how much matter is contained in a certain volume of a substance.of a substance.


Physical Properties, Physical Properties, continuedcontinued Density is often measured in units of g/cmDensity is often measured in units of g/cm33

• The equation for density is D = m/VThe equation for density is D = m/V• Density = mass/volumeDensity = mass/volume

• The density of a liquid or solid is usually reported The density of a liquid or solid is usually reported in units of grams per cubic centimeter (g/cmin units of grams per cubic centimeter (g/cm33))


Equation for DensityEquation for Density


Math SkillsMath SkillsDensity Density If 10.0 cmIf 10.0 cm33 of ice has a mass of 9.17 g, of ice has a mass of 9.17 g,

what is the density of ice?what is the density of ice?

1. List the given and unknown values.1. List the given and unknown values.Given: Given:

Unknown:Unknown:


Physical Properties, Physical Properties, continuedcontinued Physical properties help determine uses.Physical properties help determine uses.

• Examples of useful physical properties include:Examples of useful physical properties include:• low freezing pointlow freezing point• high boiling pointhigh boiling point• water resistancewater resistance• flexibilityflexibility• electrical conductorelectrical conductor• heat conductor heat conductor


Chemical PropertiesChemical Properties Chemical properties describe how a substance Chemical properties describe how a substance

reacts or how a substance changes into a new reacts or how a substance changes into a new substance when in contact with other elements.substance when in contact with other elements.

Reactivity Reactivity the ability of a substance to combine the ability of a substance to combine chemically with another substancechemically with another substance

Flammability Flammability the ability of a substance to react in the ability of a substance to react in the presence of oxygen and burn when exposed to the presence of oxygen and burn when exposed to a flamea flame


ReactivityReactivity


Comparing Physical and Comparing Physical and Chemical PropertiesChemical Properties

Characteristic properties help to identify and Characteristic properties help to identify and classify substances.classify substances.• The table below compares some physical and The table below compares some physical and

chemical properties.chemical properties.


Comparing Physical and Comparing Physical and Chemical PropertiesChemical Properties


Section 3 Changes of Matter

ObjectivesObjectives

ExplainExplain physical change, and give examples of physical change, and give examples of physical change.physical change.

ExplainExplain chemical change, and give examples of chemical change, and give examples of chemical changes.chemical changes.

Compare and contrastCompare and contrast physical and chemical physical and chemical changes.changes.

DescribeDescribe how to detect whether a chemical change has how to detect whether a chemical change has occurred.occurred.

Chapter 2

Physical ChangesPhysical Changes Physical change Physical change a change of matter from one a change of matter from one

form to another without a change in chemical form to another without a change in chemical propertiesproperties

• Physical changes affect only the physical Physical changes affect only the physical properties of a substance.properties of a substance.

Section 3 Changes of MatterChapter 2

Physical Changes, Physical Changes, continuedcontinued Dissolving is a physical change.Dissolving is a physical change.

• When a substance dissolves, the molecules of the When a substance dissolves, the molecules of the substance do not change.substance do not change.

• Dissolving a solid in a liquid, a gas in a liquid, or a Dissolving a solid in a liquid, a gas in a liquid, or a liquid in a liquid are all physical changes.liquid in a liquid are all physical changes.


Physical Changes, Physical Changes, continuedcontinued Mixtures can be physically separated.Mixtures can be physically separated.

• Because mixtures are not chemically combined, Because mixtures are not chemically combined, each component of the mixture has the same each component of the mixture has the same chemical makeup it had before the mixture was chemical makeup it had before the mixture was formed. formed.

• Mixtures can be separated based on their physical Mixtures can be separated based on their physical properties. properties.


Separating MixturesSeparating Mixtures


Chemical ChangesChemical Changes Chemical change Chemical change a change that occurs when a a change that occurs when a

substance changes composition by forming one substance changes composition by forming one or more new substancesor more new substances

• Examples of chemical changes include: Examples of chemical changes include: • burningburning• rustingrusting• digestingdigesting• decomposingdecomposing


Chemical ChangesChemical Changes


Chemical Changes, Chemical Changes, continuedcontinued Chemical changes form new substances that Chemical changes form new substances that

have different properties.have different properties.

• The results of a chemical change are substances The results of a chemical change are substances that have completely different properties from the that have completely different properties from the properties of the original substances.properties of the original substances.


Chemical Changes, Chemical Changes, continuedcontinued Chemical changes can be detected.Chemical changes can be detected.

• Changes in physical properties can be an Changes in physical properties can be an indication of a chemical change.indication of a chemical change.

• Examples include: Know these!Examples include: Know these!• change of colorchange of color• change of smellchange of smell• fizzingfizzing• production of heatproduction of heat• production of soundproduction of sound• production of lightproduction of light


Chemical Changes, Chemical Changes, continuedcontinued Chemical changes cannot be reversed by Chemical changes cannot be reversed by

physical changes.physical changes.

• Because new substances are formed in a chemical Because new substances are formed in a chemical change, the change cannot be reversed by using change, the change cannot be reversed by using physical changes.physical changes.

• Many chemical changes are impossible to reverse, Many chemical changes are impossible to reverse, for example it is impossible to for example it is impossible to ““unbakeunbake”” a cake. a cake.


Chemical Changes, Chemical Changes, continuedcontinued Compounds can be broken down through Compounds can be broken down through

chemical changes.chemical changes.

• Some compounds undergo chemical changes to Some compounds undergo chemical changes to form elements, others break down to form simpler form elements, others break down to form simpler substances.substances.


Comparing Physical and Comparing Physical and Chemical ChangesChemical Changes


Documents

Matter Chapter 2 Modified from Holt, Rinehart, and Winston presentation for textbook Science Spectrum: Physical Science