E,C,ME,C,M

Notes 10Notes 10

ElementsElements The simplest form of matterThe simplest form of matter

Simple substanceSimple substance

One kind of One kind of atomsatoms

Represented by -One or two letter symbolRepresented by -One or two letter symbol

Building blocks for all other substancesBuilding blocks for all other substances ( what things ?)( what things ?)

CompoundsCompounds Made up of two or more elements chemically Made up of two or more elements chemically

combinedcombined

Represented by chemical formulasRepresented by chemical formulas

Sodium + chlorine Sodium + chlorine sodium chloride NaCl sodium chloride NaCl

HH22O O H H22 + O + O2 2

Always present in the same ratio in a compoundAlways present in the same ratio in a compound

MIXTURESMIXTURES

Two or more substances Two or more substances physically combined physically combined do not do not

combine in same ratioscombine in same ratios

can be separated by physical can be separated by physical meansmeans

constituent substances retain constituent substances retain their original propertiestheir original properties

(salt & water - salt water)(salt & water - salt water)

MIXTURESMIXTURESHomogeneousHomogeneous

uniform composition uniform composition called “solutions”called “solutions” Salt water, alloys, etc.Salt water, alloys, etc. consist of a single phaseconsist of a single phase Alloy – mixture of two or more Alloy – mixture of two or more

metalsmetals

HeterogeneousHeterogeneous Not uniformNot uniform Sand and salt, oil and vinegar, Sand and salt, oil and vinegar,

etc.etc. consists of two or more phasesconsists of two or more phases Any part of a system Any part of a system

with uniform with uniform composition and composition and properties is called a properties is called a phasephase. .

There are many ways to There are many ways to separate mixtures, one separate mixtures, one

method is method is DISTILLATIONDISTILLATION, where a , where a liquid is boiled to produce liquid is boiled to produce vapor that is condensed vapor that is condensed

again into a liquid.again into a liquid.

PURE SUBSTANCESPURE SUBSTANCES

PURE SUBSTANCES ARE Elements or PURE SUBSTANCES ARE Elements or CompoundsCompounds

Classification of MatterClassification of Matter

MATTER

Can it be physicallySeparated ?

yes no

mixture Pure substance

Is it uniform?yes no

Homogeneoussolution

Heterogeneous

Can it be chemically separatedye

sno

compound element

Pure Substances and Pure Substances and MixturesMixtures