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 homogeneous
or heterogeneous.
•Mixtures can be separated into pure
substances, and pure substances can be
either compounds or elements.
MATTER
No
Is it uniform
throughout?
Heterogeneous
mixture
Homogeneous
No
Can it be separated
by physical means?
Pure Substance
No
Can it be decomposed
into other substance by
a chemical process?
Element
Yes
yes
Homogeneous
Mixture (solution)
yes
Compound
Section 1
Notes
Elements
* Lab
* 2 wksts
* Quiz
Pure substance
Only one type
of particle
Called Atoms
Characteristic Properties
Boiling
Point
Categories
Melting
Point
Density
Chemical
Properties
Metals
Nonmetals
Help you identify
a specific element
EX:
reactivity
with acid
Metalloids
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 2
* Lab
* Quiz
Notes
Pure substance
Compounds
Made of elements
Properties
Chemically
combined
Elements join
in specific ratios
Physical
Chemical
Used to identify
compounds
Use chemical
change to break
down to elements
or simpler
compounds
Found everywhere
Food
Clothing
Proteins
Add energy by
heat or electricity
EX: Mass of Hydrogen
to the mass of Oxygen
in water is 1 to 8 or 1:8 Ex: Sodium reacts violently with water.
Chlorine is a poisonous gas.
Combined they make sodium chloride
(table salt)
Aluminum
oxide
Ammonia
Carbon dioxide
carbohydrates
Compound – a substance made up of atoms of two or more different
elements joined by chemical bonds.
Section 2
Notes
Familiar Compounds
Compound
Elements combined
Table Salt
Sodium and Chlorine
Water
Hydrogen and Oxygen
Vinegar
Hydrogen, Carbon, and
Oxygen
Carbon and Oxygen
Carbon Dioxide
Baking Soda
Sodium, Hydrogen,
Carbon, and Oxygen
Section 3
* 4 worksheets
* Lab
* Test
Notes
Mixtures
Properties
Suspensions
No chemical
changes
happens
No
specific
ratio
Some are easy
to separate,
some are hard
Ex:
Pizza toppings,
salt water
Particles
are large
enough to
settle and
scatter/block
light
Can be
separated
by filtering
Ex: Snow Globes
Salad dressing
Solutions
Colloids
Can’t be
separated
by filtering
doesn’t
settle out
Ex:
Milk,
Mayo,
Gelatin,
Whipped
cream
Particles are smaller
than in a suspension
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.
Section 3
Notes
Mixtures and Compounds
Mixtures
Compounds
Made of elements,
compounds, or both
Made of elements
No change in original
properties of
components
Separated by physical
means
Change in original
properties of
components
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.
Substance in which
another substance
is dissolved or
the larger amount of
liquid or gas:
Solvent
Alloys:
solid solutions
metal & metal or
nonmetal & nonmetal
Substances must
be soluble to create
a solution.
Substances
that dissolve:
Solute
Ex: salt water
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
Section 3
Notes
Examples of Different States of Solutions
States
Examples
Gas in gas
Solid in liquid
Dry air (oxygen in
nitrogen)
Soft drinks (carbon
dioxide in water)
Antifreeze (alcohol in
water)
Salt water (salt in water)
Solid in solid
Brass (zinc in copper)
Gas in liquid
Liquid in liquid
Section 3
Notes
Concentrations of Solutions
Expressed in
grams of solute
per milliliter
of solvent
either
Dilute
Solubility
Ex: just the right
amount of sugar
can be completely
dissolved in water
Dissolving
Gases
in Liquids
Crushing
Less soluble as
temperature is raised
Concentrated
Does not tell the amount
of solute dissolved
Dissolving
Solids faster
in Liquids
Ex. Soft Drinks
go ‘flat’ faster when
they are warm.
Heating
Mixing
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.