Chapter Two

Matter and Change

Properties of Matter

• Matter is anything that has a mass and takes up space

• Mass is the amount of matter an object contains

• Mass is different from weight because weight depends upon gravity. For example, mass on moon is same as earth, but weight is 1/6 of that on earth.

States of Matter

Expansion on heating

VolumeShape

greatindefiniteindefiniteGas

moderatedefiniteindefiniteLiquid

very slightdefinitedefiniteSolid

Solid Liquid Gas

Plasma as a 4th state of matter

• In physics and chemistry, plasma (also called an ionized gas) is an energetic gas-phase state of matter in which some or all of the electrons in the outer atomic orbitals have become separated from the atom or molecule. The result is a collection of ions and electrons which are no longer bound to each other. This state of matter was first identified by Sir William Crookes in 1879, and dubbed

"plasma" by Irving Langmuir.

• Example: Fire, lightning, sun

States of Matter

• Solid- Matter with definite shape and volume. Coal,ice,iron,

• liquid-A form that flows, has a fixed volume, and takes the shape of its container. Water,milk,blood,

• Gas-Takes the shape and volume of its container. Air, carbon dioxide

Physical and Chemical Properties

• A physical property is a quality or condition of a substance that can be observed without changing the substance’s composition.– Intensive: depends upon internal make-up. – Size is not a factor: Example: color– Extensive: depends upon the amount of the

substance…external Example: length, mass

Chemical Property

• Chemical property: describes how a substance reacts.

• Example: rusting, burning

                                              

                                                                                                                        

An egg is cracked but hasn’t changed it’s composition.

Food coloring is mixed with water, it dissolved, this is an example of a physical change.

Ice melts and turns solid to liquid.

Water boils and turns liquid to gas.

Physical Change- alters a given material without changing it’s composition.

Chemical Changes

• A new substance is created.

• Example: Paper burns into ash

Matter, Compounds, and Elements

E lem en tE xam p les :

iron ,carb on ,su lfu r,oxyg en

C om p ou n dE xam p les :wate r,

iron su lfid e ,b erylliu m

S u b s tan ceD efin ite com p os it ion

(h om og en eou s )

H om og en eou sU n ifo rm th rou g h ou t

A lso ca lled a so lu tion .E xam p les :a ir,tap wate r

H eterog eou sN on u n ifo rm ;

D is tin c t p h asesE xam p les :sou p ,con c re te ,

M ixtu re o f su b s tan cesvariab le com p os it ion

M atte r

Elements and Compounds

• Elements are the simplest forms of matter that can exist under normal lab conditions.

• Compounds are substances that can be separated into simpler substances only by chemical means.

                             

Mixture- a physical blend of two or more substances.

Heterogeneous- one that is not uniform in composition, different throughout

Homogeneous- one that is completely uniform in composition, the same throughout.

Heterogeneous Homogeneous

Classifying Mixtures

• A mixture is a physical blend of two or more substances.

• Heterogeneous-A mixture not uniform in composition

• Homogeneous-A mixture completely uniform in composition

• Solution-Any gases, liquids,or solids.

Separating mixtures• Distillation is when a liquid is boiled to

produce a vapor and then condensed to form a liquid.

• This separates the water from what is dissolved in it.

Symbols and Formulas

• Chemical symbol-A one or two letter symbol representing the element’s name.

• Sodium-Na

• Potassium-K

• Gold-Au

• Tin-Sn

Changing Reactants to Products

• Chemical reaction-One or more substances change into new substances.

• Reactants-The starting substances in a chemical reaction

• Products-Substances formed in a chemical reaction

• Chemical property-The ability of a substance to undergo a chemical reaction and to form new substances.

Conservation of Mass

• Law of conservation of mass-In a chemical reaction or physical change the mass of the reactants stays constant with the mass of the products.

Universe Classified

• Matter is the part of the universe that has mass and volume

• Energy is the part of the universe that has the ability to do work

• Chemistry is the study of matter– The properties of different types of matter– The way matter behaves when influenced by

other matter and/or energy

Classification of Matter• Three States(Phases) of Matter:Three States(Phases) of Matter:

Solid (s)Solid (s) Liquid (l) Gas (g)Liquid (l) Gas (g)State Shape Volume Compress Flow

Solid Keeps Shape

Keeps Volume

No No

Liquid Takes Shape of Container

Keeps Volume

No Yes

Gas Takes Shape of Container

Takes Volume of Container

Yes Yes

States(Phases) of Matter

Gas (Vapor)

Liquid

Solid (Crystal)

Vaporization (Evaporization)

Fusion (Melting)

Condensation

Crystallization (freezing)

Solid to Gas Sublimation

Energy

Low

High

Properties

• Characteristics of the substance under observation

• Properties can be either directly observable orthe manner something interacts with other substances

in the universe

Properties of Matter• Physical Properties: • Characteristics of substances that

change without the substance becoming a different substance.

• Examples:• Melting Point, Boiling Point, Density,

Structure, Odor, Volume, Phase of Matter,• Color, volatility

Properties of Matter

• Chemical Properties:

• The ability of substances to change into a different substance.

• Examples: Reactivity, Flammability, polarity

Changes of Matter

• Physical Changes: • A change in the arrangement of the

molecules in matter. Does not result in new matter forming.

• Examples:• Melting, Boiling, Freezing, Condensing,

Grinding, Dissolving, Crumbling, Tearing, Mixing

Changes in Matter

• Chemical Changes:• A change in which the atoms rearrange

and form new substances.

• Examples:• tarnishing, burning, rusting, fermenting,

producing, decomposing, reacting, cooking, spoiling

Classify Each of the following as Physical or Chemical Properties

The boiling point of ethyl alcohol is 78°C.– Physical property – describes inherent characteristic of

alcohol – boiling point

Diamond is very hard.– Physical property – describes inherent characteristic of

diamond – hardness

Sugar ferments to form ethyl alcohol.– Chemical property – describes behavior of sugar –

forming a new substance (ethyl alcohol)

Matter

Elements

Pure Substances Mixtures

Compounds Homogeneous

(Solutions)

Heterogeneous

Physically combined

Chemically Combined

Classification of Matter

• Pure Substances:

• Matter that has the same composition throughout.

• Mixtures:

• Matter that has varying composition.

Pure Substances Element:Element: A substance that cannot be A substance that cannot be

decomposed into simpler substances by decomposed into simpler substances by chemical means.chemical means.

Compound:Compound: A substance with a A substance with a constant composition that can be constant composition that can be broken down into elements by chemical broken down into elements by chemical processes.processes.

Types of Mixtures• AA homogeneous mixture homogeneous mixture

• Also known as a Also known as a solutionsolution..

• The components are in the same phase, The components are in the same phase, (s,l,g) throughout(s,l,g) throughout

• Example: salt water, vinegar, coffee, air, Example: salt water, vinegar, coffee, air, alloys of metalsalloys of metals

Types of Mixtures

• AA heterogeneous mixture heterogeneous mixture

• non-uniform, contains regions with different properties than other regions

• Examples: a bottle of ranch dressing, Examples: a bottle of ranch dressing, blood, soil, oil/vinegarblood, soil, oil/vinegar

Separation of Mixtures• Can be isolated by separation methods that Can be isolated by separation methods that

utilize varying physical properties.utilize varying physical properties.

• -- ChromatographyChromatography• Uses differences in the ability of a compound to move through a substance.Uses differences in the ability of a compound to move through a substance.

• -- FiltrationFiltration• Uses differences in the size of substancesUses differences in the size of substances

• -- DistillationDistillation• Uses differences in the temperature substances evaporateUses differences in the temperature substances evaporate ....

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Thermometer

Vapors

Distillingflask

Burner

Condenser

Receivingflask

Distillate

Water out Coolwater in

Distillation Apparatus