Classification of Matter Notes

Report
PSc.2.1 OBJECTIVE: Understand
types, properties and structure of
matter.
Objectives
 PSc.2.1.1
– Classify matter as: homogeneous
or heterogeneous; pure substance
or mixture; element or compound;
metals, nonmetals or metalloids;
solution, colloid or suspension.
SHOE CLASSIFICATION
ACTIVITY
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Matter Flowchart
MATTER
yes
Can it be
physically
separated?
MIXTURE
yes
Is the
composition
uniform?
Homogeneous
Mixture
(solution)
PURE SUBSTANCE
no
Heterogeneous
Mixture
Colloids
no
yes
Can it be
chemically
decomposed?
Compound
Suspensions
no
Element
Homogeneous vs Heterogeneous
 If
matter is not uniform
throughout, then it is a
heterogeneous.
 If matter is uniform throughout, it
is homogeneous.
Homogeneous Matter
 Salt
water, apple juice and dust free air
(mixture of nitrogen, oxygen, argon,
carbon dioxide,
water vapor and other
gases) are examples
of homogeneous
materials.
Homogeneous Matter
 Brass
(solid mixture of copper and
zinc) is also homogeneous.
 Brass is an alloy, which is a mixture
of metals.
Heterogeneous Matter
 Oil-and-vinegar
salad dressing, which
has a layer of oil floating on a layer of
vinegar, is heterogeneous.
Homogeneous vs.
Heterogenous Matter
 Classify
the following substances and
mixtures as either homogeneous or
heterogeneous.
 Flat soda pop, cherry vanilla ice cream,
salad dressing, sugar, soil, aluminum
foil, black coffee, sugar water, city air,
paint, alcohol, iron, beach sand, pure
air, spaghetti sauce.
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Homogeneous vs.
Heterogeneous Matter
Homogeneous
 Sugar
 Aluminum foil
 Black coffee
 Sugar water
 Iron
 Pure air
 Alcohol
 Flat soda pop
Heterogenous
 Cherry vanilla ice cream
 Salad dressing
 Soil
 City air
 Paint
 Beach sand
 Spaghetti sauce
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Pure Substances
A
pure substance always has the
same composition.
 Pure substances are either elements
or compounds.
Elements
 Elements
are
substances that
cannot be broken
down into other
substances
chemically or
physically.
 Examples include
sodium, carbon
and gold.
Elements

Elements
– composed of identical atoms
– Ex: copper wire, aluminum foil
Compounds

Compound
– composed of 2 or
more elements in a
fixed ratio
– properties differ
from those of
individual elements
– Ex: table salt
Compounds
 Another
example of a compound
includes water (hydrogen and
oxygen).
Mixtures
A
mixture can be defined as
something that has variable
composition.
 Soda is a mixture (carbon dioxide is
dissolved in it), and coffee is a
mixture (it can be strong, weak or
bitter).
Heterogeneous Mixtures
A
heterogeneous mixture contains
regions that have different
properties from those of other
regions.
 When we pour sand into water, the
resulting mixture contains two
distinct regions.
Homogeneous Mixtures
 Homogeneous
mixtures (also known
as solutions) are mixtures in which
the composition is uniform, there are
no chunks or layers.
Substances vs. Mixtures
 Classify
the following as to whether it is
a substance or a mixture.
 Sodium, water, soil, coffee, oxygen,
alcohol, carbon dioxide, cake batter, air,
soup, iron, salt water, ice cream,
nitrogen, eggs, blood, table salt, nail
polish, milk, cola
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Substances vs. Mixtures
Substances
 Sodium (Na)
 Water (H2O)
 Oxygen (O2)
 Carbon Dioxide (CO2)
 Iron (Fe)
 Nitrogen (N2)
 Table Salt (NaCl)
Mixtures













Soil
Coffee
Cake batter
Air
Soup
Salt water
Ice cream
Eggs
Blood
Nail polish
Milk
Cola
Alcohol
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Identification Activity
 Classify
the contents of each bag as an
element, compound, or mixture.
 Justify your answers.
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Pure
Substances
and Mixtures
Question
Classify each of the following
as a pure substance, a
homogeneous mixture or a
heterogeneous mixture.
A. gasoline
homogeneous mixture
B. copper metal
pure substance
Question
Classify each of the following
as a pure substance, a
homogeneous mixture or a
heterogeneous mixture.
C. a stream with gravel at the bottom
heterogeneous mixture
D. chunky peanut butter
heterogeneous mixture
Question
Classify each of the following
as a pure substance, a
homogeneous mixture or a
heterogeneous mixture.
E. a multivitamin tablet
homogeneous mixture
F. carbon dioxide gas
pure substance
Quiz
1.
2.
3.
4.
5.
_____ has mass and occupies space.
Elements _____ be broken down into
simpler substances.
Pure substances include _____ and _____.
The formula H2O formula represents a
_____ of water.
Mixtures are formed from _____
substances.
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Tyndall Effect

The Tyndall
Effect is light
scattering by
particles in a
colloid or
particles in a
fine
suspension.
Tyndall Effect
The Tyndall Effect is
shown on the left.
Solution
Colloid
Suspension
type
particle size
Tyndall Effect
“Settle out”
Example
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Mixtures

Solution
– homogeneous
– very small particles
– no Tyndall effect
– particles don’t settle
– Ex: rubbing alcohol
Mixtures

Colloid
– heterogeneous
– medium-sized
particles
– Tyndall effect
– particles don’t
settle
– Ex: milk
Mixtures

Suspension
– heterogeneous
– large particles
– Tyndall effect
– particles settle
– Ex: freshsqueezed
lemonade
Question
Classify each of the following
as a solution, colloid or
suspension.
A) mayonnaise
colloid
B) muddy water
suspension
Question
Classify each of the following
as a solution, colloid or
suspension.
C) fog
colloid
D) salt water
solution
Question
Classify each of the following
as a solution, colloid or
suspension.
E) Italian salad dressing
suspension
Quiz
1.
2.
3.
4.
A difference in what physical property
is often used to separate two
immiscible liquids?
Fog and smoke are examples of what
type of heterogeneous mixture?
What is another term for a
homogeneous mixture?
What is an alloy?
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Quiz
1.
2.
3.
4.
The temperature at
which a solid
becomes a liquid.
Ability of a substance
to burn in the
presence of oxygen.
Ability of a substance
to combine
chemically with
another substance.
Mass per unit volume
of a substance.
a.
b.
c.
d.
e.
Melting point
Boiling point
Density
Reactivity
Flammability
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