HAPPY
FRIDAY!
TAKS OBJ 3 QUIZ
NOTES MIXTURES,
SOLUTIONS, and SOLUBILITY
MATTER
WHAT IS MATTER?
Atoms are matter
• Carbon is an element
• Elements are made of atoms
• Diamonds are made of atoms of
the element Carbon
• Foil is made of the atoms of the
element Aluminum.
Atoms are matter
• Elements most abundant in the
earth and human body are:
Element
• Pure substance that consists
entirely of one type of atom
• Hydrogen
sulfur
magnesium
COMPOUNDS
• 2 or more elements combine
to make a compound
• Nylon is an example of a
compound
• Nylon contains atoms of Carbon,
Hydrogen, Nitrogen, and Oxygen,
but each strand actually contains
hundreds of these units linked
together.
Compounds…
• Compounds are different from
the elements in which they
contain.
Molecules
• Smallest unit of a substance
that exhibits all of the
properties characteristic of that
substance
• They act as a unit
• Example: water H2O
Molecules
• Most molecules are made of
atoms of different elements, but
some can be made of atoms of
the same element.
Pure Substance
• Any matter that has a fixed
composition and definite
properties
• In Chemistry, a pure
substance is MATTER WITH
A FIXED COMPOSITION AND
DEFINITE PROPERTIES
Pure Substance
vs. Mixture
• When people say “Pure Grape
Juice” this means it contains
only the juice of the grapes with
NOTHING added or taken away
• In reality, grape juice is NOT a
pure substance. It is a
MIXTURE!!!
Mixture
• A combination of more than one
substance
• Grape juice is a mixture because it
contains water, sugars, acids, and
vitamins
• The composition of grape juice is
not fixed; it can have different
amounts of water, sugars, or other
compounds
Mixtures vs.
Pure Substances
• Almost all things we eat are
mixtures
• The air we breathe is a mixture of
nitrogen and oxygen
• Pure Substance: (ex: water)
• Cannot be broken down by physical
actions such as boiling, melting, or
grinding
Pure substances blended
together make mixtures
• A mixture may have some
properties similar to the pure
substances that make it
• Although you cannot see the
different substances in grape
juice, the mixture has chemical
and physical properties in
common with its components
• Ex: fluid like water; sweet like sugar
Mixtures
• There are 2 types of
mixtures that we will
deal with:
• Heterogeneous mixture
• Homogenous mixture
Heterogeneous
Mixtures
• Mixtures of this type are not
the same throughout.
• Example: Fruit Salad
• Each spoonful of fruit salad would
give you a different variety – no 2
spoonfuls would be exactly the
same.
Homogenous
Mixtures
• These mixtures are uniform,
in that no matter where you
get your sample from in the
mixture – each sample will
be the exact same.
homogeneous
heterogeneous
Mixtures classified
by how thoroughly
the substances mix
Solids + Liquids
examples to compare:
Salt + water
vs
Flour + water
Mixtures classified by how
thoroughly the substances mix
• Flour doesn’t mix very well with
water- it gives a cloudy white
mixture The flour doesn’t
dissolve in water
This is an example of a
heterogeneous mixture
because the substances
are not uniformly mixed.
Mixtures
Salt + Water
You cannot see the salt and
the mixture is clear
WHY??
−SALT DISSOLVES IN WATER
Even if you leave the mixture
for a long time, the salt will
not settle out.
This is an example of a:
homogenous mixture
Mixing between the individual
units and is the same throughout.
Obj. 1 cont…
Pure or Mixture?!?!
1. Kool-aid
mixture
2. distilled water
3. tap water
pure
mixture
mixture
4. chocolate chip cookie
5. oxygen gas
6. atmosphere
pure
mixture
7. Glucose (C6H12O6)
pure
CLASSIFYING MATTER
Elements
Pure
Substance
Compounds
MATTER
Homogeneous
Mixtures
Heterogeneous
Solutions and
Homogenous mixtures
SOLUTIONS & HOMOGENOUS
MIXTURES are synonymous.
Homogenous mixtures are mixed
completely, all the way down to
their most fundamental particlesatoms, molecules, or ions.
Mixtures
• Gasoline is a liquid
mixture…
• A homogenous mixture of at
least 100 compounds in various
quantities
• The compounds within gasoline
are miscible, thus gasoline
looks like a pure substance
even though it is not.
MISCIBLE
Describes 2 or more
liquids that are able to
dissolve into each other in
various proportions
Ex: Water and
Rubbing alcohol
IMMISCIBLE
• If you shake a mixture of oil and
water, the water will settle out
after a while.
• Oil and water form a
heterogeneous mix
• Oil and Water are immiscible
thus you can see layers in the
mixture.
IMMISCIBLE
• 2 or more liquids that do
NOT mix into each other
Gases can mix with
liquids
• Carbonated drinks are
homogeneous mixtures.
• They contain sugar, flavorings,
and CO2 gas, dissolved in water.
• When carbonated drinks are
manufactured, the CO2 gas is
mixed into the liquid under
pressure and forms a solution.
Gases can mix
with liquids
• Liquids not under pressure
can also contain dissolved
gases.
• If you let a glass of ice water sit
out over night, you may see
bubbles on the sides of the glass
the next morning. The bubbles are
some of the air that was dissolved
in the cold water.
2.1 Section Review
On a separate sheet of notebook
paper answer the following questions:
1: List the 2 types of pure substances
2: Complete the following:
A heterogeneous mixture is to a homogeneous
mixture as immiscible liquids are to _______.
3: Classify each as an element or mixture:
Sulfur (S8); Carbon Monoxide(CO); Methane (CH4)
4: Give an example of a mixture and a pure substance.
Solutions and
Other Mixtures
(Ch 6-1 and 6-2)
OBJECTIVES
• Homogeneous vs. Heterogeneous
mixtures
• Compare and Contrast:
solutions, colloids, suspensions
• Identify ways to separate mixtures
CLASSIFYING MATTER
Elements
Pure
Substance
Compounds
MATTER
Homogeneous
Mixtures
Heterogeneous
Solutions and
Homogenous mixtures
SOLUTIONS & HOMOGENOUS
MIXTURES are synonymous.
Homogenous mixtures are mixed
completely, all the way down to
their most fundamental particlesatoms, molecules, or ions.
Solutions and
Other Mixtures
• Heterogeneous Mixtures
• Ex: Fruit Salad
− NOT the same throughout
− Quantity of each fruit varies with each
spoonful
Heterogeneous Mixture
SUSPENSION
• Have you ever forgotten to
shake the OJ bottle before you
poured a glass?
• Probably tasted watery
• Due to suspensions of orange pulp in
OJ, which is mostly water
SUSPENSION
a mixture that
looks uniform
when stirred or
shaken that
separates into
different layers
when it is no
longer agitated
Suspension
• SUSPENSIONS a mixture that looks
uniform when stirred or shaken that
separates into different layers when it is
no longer agitated
• OJ:
• If carton is not shaken, then
the pulp goes to the bottom
and the watery liquid sits on
top.
Suspension
• Not all OJ has pulp
• It can be separated out
• Particles in suspensions are
usually large enough they can be
filtered out of mixture
− (pulp stays behind)
Solution
Suspension
• All components are
evenly distributed
• dissolved
• (salt in water)
Mixture of water
and nondissolved
materials
(flour in water)
COLLOID
• Gelatin  heterogeneous mix
• Gelatin is a colloid
• Colloid a mixture of very tiny
particles of pure substances that
are dispersed in another
substance but do not settle out
of the substance
Colloids
• Differences between suspensions
and colloids:
• Particles in colloids are much smaller
• Because they are so small, they do NOT
separate out or settle to the bottom in
colloids
• Particles stay dispersed throughout the
mixture
Colloids
• EXAMPLES:
• Egg white
• Paint
• Blood
• Whipped cream (dispersing gas in a
liquid)
• Marshmallows (dispersed gas in a
solid)
Heterogeneous
liquid-liquid mixtures
• Oil + vinegar  2 layers
• They are immiscible
• Oil floats on vinegar b/c less dense
• To separate mixture:
• Cup with spout
• Cooks use this to
separate fat from
meat juices; fat is
less dense thus stays
behind in the cup
Some immiscible
liquids can mix in
EMULSIONS
EMULSION:
Any mixture of
immiscible liquids
in which the
liquids are spread
throughout one
another
Emulsions
• EXAMPLE:
• Mayonnaise mixture of oil
suspended in vinegar
− They stay mixed (unlike that in salad
dressing) because mayonnaise also
contains egg yolk
− Egg yolk coats the oil droplets keeping
them from joining to form a separate layer
− Thus, mayonnaise is an emulsion
– (colloid where liquids normally do not
mix are spread throughout each other)
Homogeneous Mixtures
• Not only look uniform, they
ARE uniform
• Ex: Salt water
• If you add salt to a glass of pure
water and mix it, it will eventually
look like pure water
• Looks uniform because the
components of the mixture are too
small to be seen
Homogeneous Mixtures
• When salt and water mix, no
chemical reaction takes place
• Easy to separate the 2 substances by
evaporating or boiling the water
• Once boiled, only left with salt
Solutions are
Homogenous Mixtures
• When you add aquarium salt
to water and stir, the solid
seems to disappear.
• What is really happening??
Solutions are
Homogenous Mixtures
• The solid DISSOLVES in
water to form a solution
• In this example, the
aquarium salt is the
solute, and the water is
the solvent.
Solute and Solvent…
• A SOLUTE is the
substance that
DISSOLVES in a
solution.
• A SOLVENT is the
substance that
dissolves the solute to
make a solution.
SOLUTIONS
• When a solute completely
dissolves in a solution, the
dissolved particles are so
small that you cannot see
them
• Solutes and solvents can
be in any state of matter.
SOLUTIONS
• Ex:
• VINEGAR  A solution of Acetic
Acid, a liquid, dissolved in water,
another liquid
• A tank of air used by a scuba
diver can be thought of as a
solution of oxygen and several
other gases.
Miscible Liquids 
mix to make solutions
Water + Isopropanol  rubbing alcohol
(both liquids)
Acetic Acid + Water 
solution
Vinegar
Miscible Liquids
• Since miscible liquids
DO NOT separate into
layers, they do not
separate as easily as
immiscible liquids do.
• One way to separate
miscible liquids is by
distillation
Miscible Liquids
• Distillation is the easiest way
to separate two miscible
liquids
• Distillation can be used when
wanting to separate water and
methanol
− Boiling points of the 2 are significantly
different
− BP WATER = 100
− BP Methanol = 67
Distillation
1. heat entire mixture until
it boils
2. Liquid with lower boiling
point would vaporize first
(methanol @ 67 deg)
3. Some water would
vaporize, but most would
stay behind
Chromatography
• If 2 miscible liquids have
similar boiling points it
can be even harder to
separate by distillation
• Chromatography can be
used anytime it is too
difficult to separate by
distillation
Chromatography
the science which studies the
separation of molecules based on
differences in their structure and/or
composition.
Chromatographic separations can be carried out
using a variety of supports, including:
immobilized silica on glass plates
(thin layer chromatography)
volatile gases (gas chromatography)
paper (paper chromatography)
and liquids which may incorporate hydrophilic
insoluble molecules (liquid chromatography).
DISSOLVING AND
SOLUBILITY
DISSOLVING AND
SOLUBILITY
Dissolving Rate
• Factors that affect dissolving
rate of a solute in a solvent
• Can you think of any on your
own???
SURFACE AREA
• Solutes with a larger
surface area dissolve
faster
A substance in small pieces
dissolves faster than the same
substance in big pieces
• EXAMPLE:
− Loose sugar vs. Sugar cube
− Chewable Vitamin C vs. pill swallowed
Shaking or Stirring
If you pour sugar in a glass and let it sit
without stirring, it will take longer for the
sugar to dissolve completely
--sugar sitting at the bottom of the glass is surrounded by dissolved sugar
molecules – these molecules will slowly diffuse throughout the solution
Until they spread through the entire solution the dissolved sugar keeps the
water molecules from reaching the sugar crystals that haven’t dissolved yet.
Shaking or Stirring
If you pour sugar in a glass and let it sit
without stirring, it will take longer for the
sugar to dissolve completely
stirring or shaking the solution moves the dissolved sugar
away from the sugar crystals. Now more water
molecules can interact with the solid,
so the sugar crystals
dissolve faster.
TEMPERATURE
• Sugar and other solutes
dissolve faster in HOT
water than in cold
water.
• Remember, that as a substance is
heated, its particles move faster
• As a result there are more
collisions between particles and
each collision transfers energy
TEMPERATURE
• For gases, it is different…
• Solubility is INVERSELY
PROPORTIONAL to temperature for
gases
• The lower the temperature of the
solvent, the higher the solubility
• EX: Hot sodas will go flat!!
PRESSURE
DOES NOT affect the
solubility of solids!!!
The solubility of a gas is
affected by pressure…
• Solubility is DIRECTLY
PROPORTIONAL to pressure for
gases
− The HIGHER the pressure, the
HIGHER the solubility
− Think SCUBA divers and their gas
NOT EVERY
SUBSTANCE WILL
DISSOLVE
• If a solute DISSOLVES in a
solvent then it is said to be
SOLUBLE
• Example: Salt in Water
• If a solute DOES NOT DISSOLVE
in a solvent then it is said to be
INSOLUBLE
• Example: Olive Oil in water
– They form two separate layers
Water
• Most abundant compound in
most living things!
WATER:
A common Solvent
• 2/3 of the Earth’s surface is water
• Liquids we drink mostly water
• ¾ of body weight is water
• Many substances can dissolve in
water therefore,
WATER IS THE UNIVERAL SOLVENT!!!
WATER
• Water is the universal
solvent
• The structure of water helps
it dissolve charged particles
• Water is polar – uneven
distribution of electrons
Hydrogen Bonding
• Polarity causes attraction
WATER = THE Universal Solvent
The figure below shows why NaCl easily
dissolves in water…
• Sodium ions are attracted to the partially negative
oxygen atom, and Chloride ions are attracted to the
partially positive Hydrogen atoms
• Interactions between the ions and water molecules pull
the ions away from the solid
Like Dissolves Like
Water can dissolve MANY
substances, but not all
• EX: oil or gasoline doesn’t dissolve in water
• Methanol is soluble in water because
both liquids are polar
− They have partially charged atoms that are
attracted to one another
• Gasoline: NOT SOLUBLE in water because its
components are nonpolar
Nonpolar = molecules do not have
partial charges on opposite ends
CONCENTRATION
Solutions can have different
concentrations depending on how much
solute and solvent are present
CONCENTRATION
CONCENTRATION 
THE QUANTITY OF SOLUTE
DISSOLVED IN A
GIVEN
QUANTITY OF SOLUTION
CONCENTRATION
If a small quantity of solute is dissolved in
a large volume of solvent, the resulting
solution is said to be dilute
A concentrated solution has a large
quantity of solute dissolved in the
solvent.
Saturated Solutions
• Saturated Solution: contains the
greatest quantity of solute that will
dissolve in a given quantity of solvent
• SOLUBILITY: the greatest quantity of a
solute that will dissolve in a given
quantity of solvent to produce a
saturated solution
SOLUBILITY
Solubility  the maximum amount
of a solute that can be dissolved in a
given solvent at a certain temperature
and pressure
Try thinking of it like “solute capacity”, like the seating of
a restaurant
-solubility = seating capacity
- solute = people
- solvent = seats
EVERY “restaurant” (or solvent) is different!!!
Saturated and
Unsaturated Solutions
Unsaturated Solution 
• a solution that is able to dissolve more
solute
Saturated Solution 
• A solution that cannot dissolve any more
solute at the given conditions
SUPERSaturated
Solutions
• Supersaturated Solution: a solution
holding more dissolved solute than is
specified by its solubility at a given
temperature
• Supersaturated solutions are unstable
systems because the solute’s solubility
is exceeded for a short time.
SUPERSaturated
Solutions
Adding a single crystal of sodium
causes the excess sodium acetate
to quickly crystallize out of the
solution until the solution is
saturated at the cooler
temperature
SUPERSaturated
Solutions
• 2 ways to bring a
supersaturated solution back to
a saturated solution…
1 heating up the solution to
dissolve more solute
2 adding more solvent to the
solution in order to dissolve the
solute