Matter And Measurement INTRODUCTION. MATTER Substance Mixture Element Matter Compound Homo- geneous...

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Anything that occupies space (has volume) and has mass

Transcript of Matter And Measurement INTRODUCTION. MATTER Substance Mixture Element Matter Compound Homo- geneous...

Matter And

Measurement

INTRODUCTION

MATTER

Substance Mixture

Element

Compound

Homo-geneousMixture

Hetero-geneousMixture

Physical Separation

Chemical Separation

Classification of Matter

Matter that has a uniform and definite composition

Substances have distinctive characteristic (identifying) physical & chemical properties

Elements & compounds are substances

PURES

BSTANCE

H2O

CO2

NaCl

Al O2

C12H22O11

examples

A substance that can not be broken down to simpler substances by chemical means

Most elements are composed of individual atoms (some elements are composed of groups of identical atoms).

ELEMENT

O2

Cu

Na

AlH2

examples

A substance composed of two or more elements

A compound can be broken down (decomposed) by chemical means

In compounds, elements are chemically bonded

COMPOUND

C12H22O11

H2OCO2

examples

A physical blend of two or more substancesM

IXTURE

Homogeneous Mixture

Heterogeneous Mixture

A mixture which is uniform and has a single phase (single state); also called a solution

A mixture which is NOT uniform and usually has more than one phase

example example

Salt & WaterSand & WaterSand & SaltSand alone

MIXTURE (Example Saltwater)

Physical blend of substancesPhysical properties of mixture are the same properties of its componentsComponents combine in any ratioSeparation is by physical process

Chemical combination (bonding) of 2 or more elementsPhysical properties of compounds are unique & different from properties of its elementsComponents (elements) combine in a definite ratioSeparation (decomposition) is a chemical process

Comparison of Mixture & Compound

COMPOUND(Example Water)

Mixture CompoundH2 (g) and O2 (g)Hydrogen Gas +

Oxygen Gas

H2O (g)Water Vapor (steam)

Extensive properties

Intensive properties

VolumeMass

Energy Content (think Calories!)

: depend on the amount of matter that is present.

: do not depend on the amount of matter present.Melting point

Boiling pointDensity

Properties of Matter

CLASSIFICATION OF MATTER

SaltSalt Water

Air Soil Blood

CLASSIFICATION OF MATTER

Sand

Water

Concrete Iron

Brass (copper & zinc)

PHYSICAL changes

Will alter a substance without changing its composition

Are frequently reversible

Properties or characteristics do not change

Will alter a substance by changing its composition

Are not frequently reversible

New substances formed have new properties or characteristics

Substances can be altered by Physical Changes or Chemical Changes

CHEMICAL changes

Exampl

es

PHYSICAL changes

DissolvingEvaporatingFreezing

Sodium + chlorine NaClsilver metal gas salty taste, white,

H2O solubleexplosive in water “green” color non flammabletoxic toxic non toxic

CHEMICAL changes

Examples

CHEMICAL CHANGE

In every chemical reaction, one or more of the following can be observed

When a chemical reaction occurs, one or more

substances is changed into new substances

Indi

cato

rs o

f a

Che

mic

al

Rea

ctio

n

Change in temperature

Change in color

Change in odor

Formation of a gas

Formation of a solid precipitateM

any

chem

ical

rea

ctio

nsar

e N

OT

reve

rsib

le

Classify each process as being a physical change only OR a process that also

involves a chemical change (chemical

reaction)

Boiling

Decomposing Dissolving

Baking

Three Phases

Solid – definite volume and shape; particles packed in fixed positions.Liquid – definite volume but indefinite shape; particles close together but not in fixed positionsGas – neither definite volume nor definite shape; particles are at great distances from one anotherPlasma – high temperature, ionized phase of matter as found on the sun.

Phase Differences