Pure Substances, Mixtures, and

Solutions

Separating Matter into 3 classifications:

•Pure substance: matter that has a fixed (constant) composition and unique properties. Contains only 1 type element or compound; homogeneous

Mixture: Contains at least 2 PHYSICALLY

combined compounds; can be homogeneous

or heterogeneous

Homogeneous Substances• Means same throughout

1) element: only 1 type of atom

2) compound: 2 or more CHEMICALLY combined elements (not easily separated from each other)

ex: water, CO2

3) Solution: a special kind of mixture 2 phases/parts (SOLUTE dissolves & SOLVENT does the dissolving)

ex: moist air (H2O in Air); sterling silver (Cu

in Ag…called an alloy)

Heterogeneous matter

• Means different throughout

• Always a MIXTURE (solutions are mixtures that are NOT heterogeneous)

• 2 or more PHYSICALLY combined substances (elements/compounds)

• ex: blood, air, muddy water

Separating Matter into 3 classifications:

•Matter can also be classified according to its composition. Mixtures can be homogeneousor heterogeneous.

•Mixtures can be separated into pure substances, and pure substances can be either compounds or elements.

MATTER

Heterogeneous

mixture

Is it uniform

throughout?

No

Homogeneous

Yes

Can it be separated

by physical means?

Pure Substance Homogeneous

Mixture (solution)Can it be decomposed

into other substance by

a chemical process?

Element Compound

No yes

No yes

ElementsPure substance

Only one type

of particle

Called Atoms

Characteristic PropertiesBoiling

Point

Melting

Point

Density Chemical

Properties

EX:

reactivity

with acid

Categories

Metals

Nonmetals

Metalloids

Help you identify

a specific element

Element – a substance that cannot be separated or broken down into simpler

substances by chemical means.

Pure Substance – a sample of matter, either a single element or a single

compound, that has definite chemical and physical properties.

Metal – an element that is shiny and that conducts heat and electricity well.

Nonmetal – an element that conducts heat and electricity poorly.

Metalloid – an element that has properties of both metals and nonmetals.

Section 1

* Lab

* 2 wksts

* Quiz

Notes

Compounds

EX: Mass of Hydrogen

to the mass of Oxygen

in water is 1 to 8 or 1:8

Compound – a substance made up of atoms of two or more different

elements joined by chemical bonds.

Pure substance

Made of elements

Chemically

combined

Elements join

in specific ratios

Properties

Physical

Chemical

Used to identify

compounds

Ex: Sodium reacts violently with water.

Chlorine is a poisonous gas.

Combined they make sodium chloride

(table salt)

Use chemical

change to break

down to elements

or simpler

compounds

Add energy by

heat or electricity

Found everywhere

Food

Clothing

Aluminum

oxide

Ammonia

Proteins

Carbon dioxide

carbohydrates

Section 2

* Lab

* Quiz

Notes

Familiar Compounds

Compound Elements combined

Table Salt Sodium and Chlorine

Water Hydrogen and Oxygen

Vinegar Hydrogen, Carbon, and

Oxygen

Carbon Dioxide Carbon and Oxygen

Baking Soda Sodium, Hydrogen,

Carbon, and Oxygen

Section 2 Notes

MixturesProperties

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

combined.

Suspension – a mixture in which particles of a material are more or less evenly

dispersed throughout a liquid or gas.

Colloids – a mixture consisting of tiny particles that are intermediate in size

between those in solutions and those in suspensions and that are suspended in a

liquid, solid or gas.

No chemical

changes

happens

Some are easy

to separate,

some are hard

Ex:

Pizza toppings,

salt water

No

specific

ratio

Suspensions

Solutions

Colloids

Particles

are large

enough to

settle and

scatter/block

light

Can be

separated

by filtering

Ex: Snow Globes

Salad dressingParticles are smaller

than in a suspension

Ex:

Milk,

Mayo,

Gelatin,

Whipped

cream

Can’t be

separated

by filtering

doesn’t

settle out

Section 3

* 4 worksheets

* Lab

* Test

Notes

Mixtures and Compounds

Mixtures Compounds

Made of elements,

compounds, or both

Made of elements

No change in original

properties of

components

Change in original

properties of

components

Separated by physical

means

Separated by chemical

means

Formed using any ratio

of components

Formed using a set ratio

of components

Section 3 Notes

Solutions* Appears to be a

single substance.

* Particles don’t

settle – very small

* Doesn’t scatter light.

Substances

that dissolve:

Solute

Substance in which

another substance

is dissolved or

the larger amount of

liquid or gas:

Solvent

Solution – a homogeneous mixture of two or more substances uniformly

dispersed throughout a single phase

Solvent – in a solution, the substance in which the solute dissolves.

Solute – in a solution, the substance that dissolves in the solvent.

Soluble – able to dissolve

Insoluble – unable to dissolve

Substances must

be soluble to create

a solution.

Ex: salt water

Alloys:

solid solutions

metal & metal or

nonmetal & nonmetal

Section 3 Notes

Examples of Different States of Solutions

States Examples

Gas in gas Dry air (oxygen in

nitrogen)

Gas in liquid Soft drinks (carbon

dioxide in water)

Liquid in liquid Antifreeze (alcohol in

water)

Solid in liquid Salt water (salt in water)

Solid in solid Brass (zinc in copper)

Section 3 Notes

Concentrations of Solutions

Concentration – the amount of a particular substance in a given quantity of a

mixture, solution, or ore.

Dilute – a solution with less solute.

Concentrated – a solution with more solute.

Solubility – the ability of one substance to dissolve in another at a given

temperature or pressure.

Expressed in

grams of solute

per milliliter

of solvent

either

Dilute Concentrated

Does not tell the amount

of solute dissolved

Solubility

Ex: just the right

amount of sugar

can be completely

dissolved in water

Dissolving

Gases

in Liquids

Less soluble as

temperature is raised

Ex. Soft Drinks

go ‘flat’ faster when

they are warm.

Dissolving

Solids faster

in Liquids

Mixing

Heating

Crushing

Section 3 Notes