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Matter:Classification

How would you define CHEMISTRY?

� “The science that deals with the composition and properties of substances and various elementary forms of matter.”(dictionary)

� “The study of matter and its interactions.”

What IS Matter?

� Anything that has mass and takes up space.

Matter Flowchart

Can it be physicallyseparated?

yes no

noyesIs the composition uniform?

noyes Can it be chemically

decomposed?

Matter Flowchart

MATTER

Can it be physically separated?

MIXTURE PURE SUBSTANCE

yes no

Compound Element

Can it be chemically

decomposed?noyes

Organic Inorganic

Pure Substances

� ELEMENT

� composed of identical atoms

� EX: copper wire, aluminum foil, anything off the periodic table of elements

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Pure Substances

� COMPOUND

� composed of 2 or more elements in a fixed ratio

� properties differ from those of individual elements

� EX: table salt (NaCl), water (H2O)

Pure Substances

� COMPOUND

�ORGANICcontain C & H(hydrocarbons)ex: gasoline, sugar

� INORGANICeverything else ☺

Pure Substances

� Law of Definite Composition

� a given compound always contains the same, fixed ratio of elementsex: water is ALWAYS H2O

Pure Substances

� Law of Multiple Proportions

� elements can combine in different ratiosto form different compoundsex: C & O can form CO (deadly gas) or CO2

(not deadly!)

Matter Flowchart

MATTER

Can it be physically separated?

MIXTURE PURE SUBSTANCE

yes no

Compound Element

Can it be chemically

decomposed?noyes

Organic Inorganic

Homogeneous

Mixture

(solution)

Heterogeneous Mixture

Is the composition

uniform?noyes

Colloids Suspensions

Mixtures

� variable combination (not fixed) of 2 or more pure substances

Heterogeneous Homogeneous

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Mixtures

pure substanceheterogeneous

mixture

homogeneous

mixture

Pure substance, homogenous mixture, or heterogenous mixture?

heterogeneous

mixture

Pure substance, homogenous mixture, or heterogenous mixture?

pure substance

Pure substance, homogenous mixture, or heterogenous mixture?

pure substance

Pure substance, homogenous mixture, or heterogenous mixture?

pure substance

Pure substance, homogenous mixture, or heterogenous mixture?

homogeneous

mixture

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Mixtures

� HOMOGENEOUS

� aka solution

� very small particles

� no Tyndall effect

–particles don’t settle

–ex: rubbing alcohol

SOLID SOLUTION?!

� alloys are solid solns in which 2+ metals are UNIFORMLY mixed

ex: brass (zinc + copper), sterling silver (silver + copper), 14K gold (gold + silver + copper)

Mixtures

� Heterogeneous: COLLOID� medium-sized particles� Tyndall effect� particles don’t settle� ex: milk,mayo, shavingcream, whipped cream,cheese, fog,butter, clouds

Mixtures

� Heterogeneous: SUSPENSION

� large particles

�may show Tyndall effect

� particles settle

� ex: fresh-squeezed lemonade, muddywater

Mixtures Chart

translucent/opaque

Tyndall effect

transparenttransparentBehavior to light

yesnonoSettles on standing

noonly to the naked eye

yesHomogeneous

yesnonoFilterable with ordinary paper

largemediumsmallParticle size (nm)

SuspensionsColloidsSolutionsProperty

Check Yourself!

� Are the following examples an element, compound, or mixture (homog. vs hetero.)?

� graphite

� choc. chip

cookie dough

� sugar (sucrose)

� salt & pepper

� soda

element

mixture (hetero.)

compound

mixture (hetero.)

mixture (homog.)