Matter and Change
I.
Phases or States of Matter
Depends upon how much energy the matter has:
A. SOLID PHASE
1.
2.
3.
4.
B.
Has definite shape and definite volume
Regular geometric pattern
Least amount of energy
Molecules just “shiver”
LIQUID PHASE
1. Has definite volume but no definite shape
2. Takes the shape of its container
3. Contains more energy than a solid but
less energy than a gas
4. Molecules move faster than those in the
solid phase but slower than those in the
gaseous phase
C.
GAS PHASE
1. Has no definite shape and no definite
volume
2. Takes the shape of its container
3. Most amount of energy
4. Molecules move the fastest
II.
Properties of Matter
A. There are two types of properties of matter:
Physical Properties and Chemical Properties
B.
Physical Properties: observed without
changing the composition of the matter
1. Extensive physical property: depends
upon how much matter is present (mass,
volume, length, energy)
2. Intensive physical property: independent
of or does NOT depend on how much
matter is present (density, temperature,
phase, luster, color, BP, MP, solubility,
conductivity)
Definitions and Examples of Physical Properties:
• Malleability: The property displayed by certain
metals that enable them to be hammered, rolled
out into sheets, shaped, etc.
• Ex. Lead
• Ductility: The property displayed by certain
metals that enable them to be drawn into wire
without breaking
• Ex. Copper
• Hardness: The property of an object that resists
being crushed or deformed
• Ex. Diamonds
• Brittleness: The property of an object that can
be easily broken or crushed into smaller parts
under low pressure
• Ex. Talc
• Conductivity: The ability of a metal to allow an
electric current to pass through it
• Ex. Silver
• Solubility: The property of a substance that
allows it to dissolve
• Ex. Salt dissolving in water
• Melting Point
– Temperature at which a solid changes to a
liquid
• Boiling Point
– Temperature at which a liquid changes to a
gas
C.
Chemical Properties: describes how one
form of matter interacts or reacts with
another (combust, corrodes (oxidize, rot,
rust, decompose) react, flammable, explode)
Definitions and Examples of Chemical Properties:
• Combustibility/Flammability: The measure of
how easily a substance burns
• Ex. Wood is flammable, Kevlar is fireresistant
• Reactivity with other substances: The ability to
react or to not react with other chemical
substances
• Ex. Baking Soda + Vinegar react to create
Carbon Dioxide and Water
• Corrosion: The chemical reaction between a
material and its environment that produces a
deterioration of the material and its properties.
• Ex. Iron reacts with air and water to form rust
Try this?!?
Determine if the properties shown below are Chemical
or Physical? If Physical indicate intensive or extensive
• Combustibility
• Malleability
• State of Matter
• Density
• 20mL of Vinegar
• A piece of burning paper
• An Iron tractor covered in Rust
• Sulfuric Acid reacts with Sugar to get charcoal
III. Changes in Matter
A. There are two types of changes of matter:
Physical Changes and Chemical Changes
B.
Physical Change: A change in a chemicals
appearance but NOT composition
1.
2.
3.
4.
Used to separate mixtures
Do not alter the composition (makeup or identity) of the matter
Substances in mixture are still the
exact same substances they were
before the physical change
occurred
Separation techniques include
1. filtration – particle size
2. evaporation and distillation –
uses boiling pt.
3. centrifuge – density
4. magnetism – metallic property
5. decanting – solubility and
density
6. chromatography – uses
solubility or
attraction or
particle size
Examples of Physical Changes:
• Tearing, grinding, dissolving, phase changes
C. Chemical change: A change that DOES
change the identity of the substance
A.
B.
C.
DO alter the identity of the matter
Requires a minimum of two different
forms of matter in order to occur
Reactants (beginning ingredients) and
products (end form of the matter) are
different from one another
reactant + reactant → product(s)
D.
To recognize a chemical change, look for:
a. formation of gas (bubbles)
b. color change
c. precipitate (dense solid in solution)
d. sound or light energy (E) produced
e. quick change in temperature (T)
Thinking Questions?!?
1. Do you encounter chemical changes in your
everyday lives?
Answer: Baking cookies, Leaves changing color
in the fall
2. Can a change in a physical property indicate a
chemical change?
Answer: Yes, color is a physical property and color
of the beginning substances can differ
from the color of the final substance.
Remember Copper Sulfate
IV. Classification of Matter
Based on the number of different substances it
has in it
A.
Mixture – matter composed of different parts
that are physically combined
1. homogeneous mixture (solution)
a. Characteristics:
• Consistency w/in sample
• Uniform throughout
b. Example:
• Salt and water solution
2.
heterogeneous mixture
a. Characteristics:
• No consistency w/in sample
• Not uniform throughout
• Often cloudy
• Often settle upon standing
• Can usually filter to separate
b. Example:
• Sand and water mixture
3.
are NOT governed by the Law of
Definite Proportions
a. Definition:
• states that a chemical compound
always contains exactly the same
proportion of elements by mass
B.
4.
CAN be separated (purified) by physical
means
• Filtration (only for Heterogeneous
mixtures)
• Evaporation
• Distillation
• Decanting
• Crystallization
• Magnetism
5.
Do NOT combine chemically
Pure Substance – matter composed of parts
which are identical in properties and
composition
1. element – one and only one kind of
atom present
a. Characteristics:
• ALL atoms are identical
• CANNOT be broken down at ALL
• Simplest kind of matter
b. Examples:
• The ENTIRE periodic table
2.
compound (cmpd) – requires a
minimum of two kinds of atoms bonded
together per piece of substance
a. Characteristics:
• TWO or MORE elements
chemically combined and separated
• New Properties
• Examples:
- Copper Sulfate
- Sodium Chloride
Sodium (Na)
- Soft silver-colored metal
- Reacts violently with water
Chlorine (Cl2)
- Poisonous, yellow-green
gas
- Sharp odor
- Used during WWI
When combined form Table
Salt (NaCl)
- Essential to life
- Regulate water content in
our bodies
• Definite Ratio
• Ex. H2O vs. H2O2
3.
are governed by the Law of Definite
Proportions
4.
cannot be separated (purified) further by
physical means
MATTER
Is it uniform
throughout?
YES
!
NO!
HETEROgeneous
MIXTURE
HOMOgeneous
Can it be
separated by
physical means?
YES
!
NO!
PURE SUBSTANCE
HOMOgeneous
MIXTURE
(SOLUTION)
Can it be
chemically
decomposed?
NO!
ELEMENT
YES
!
COMPOUND
V.
How to distinguish among elements, compounds
and mixtures
A. Given Diagrams: see worksheet
B. Given Examples:
1. If it is on the periodic table, it is an
element
2. If it has only 1 capital letter, it is an
element
a. Chemical symbols on the periodic
table always contain ONE and only
ONE capital letter
b. Examples:
• Ba, H, Ne, Au, U, etc.
3. If it has more than 1 capital letter, it is a
compound
a. Examples:
• NaCl (salt) contains two capital
letters which means that the
compound is made up of two
different elements
• HCO3 (Baking Soda) contains three
capital letters which means three
different elements are present
4. If it has a complicated 2 word name, it is
a compound (except for: sugar, salt,
water, alcohol, ammonia)
a. Examples:
• Barium Hydroxide
• Hydrogen Peroxide
5. If you think it is chemically combined (i.e.
you can’t imagine any physical way to
separate it), it is a compound.
Otherwise, it is a mixture.
6. Homogeneous mixtures won’t settle and
are even or uniform throughout
a. Examples:
• Salt-water solution
• Sugar-water solution
7. If something is produced that has
completely different properties, then it
is a compound
a. Examples:
• Copper sulfate (Blue color)
8. If it can’t be broken down at all, then it is
an element
9. If it can only be separated chemically,
then it is a compound
10. If it can be separated physically
(boiling, distillation, magnet, filtering
(only heterogeneous)), then it is a
mixture
11. If it is (s) or (l) it is an element or
compound, if it is (aq) then it is a
homogeneous mixture
a. Example:
• NaCl(s) vs NaCl(aq)
Experimental data examples
Question #1
Two samples were sent to a lab and various tests
were performed
• Test #1
– Filtration
• Sample 1 was able to be filtered
• Sample 2 was not able to be filtered
• Test #2
– Heating
• Sample 2 was found to contain two
different Boiling Points
• What could Sample 1 be?
– Heterogeneous mixture  able to be filtered
• What could Sample 2 be?
– Homogeneous mixture  Two different
Boiling Points
Question #2
Two samples were sent to a lab and a chemical
reaction was performed
• Test #1
– Chemical Reaction
• Sample 1 did not react and was not able
to be chemically separated
• Sample 2 was able to react and be
chemically separated
• What could Sample 1 be?
– Element  Not able to be chemically
separated
• What could Sample 2 be?
– Compound  Chemically separated
Question #3
Two samples were sent to a lab and a chemical
reaction was performed
• Test #1
– Filtration
• Sample 1 was able to be filtered
• Sample 2 was not able to be filtered
• Test #2
– Heating
• After heating Sample 2, a solid was
found left behind which was tested and
found to be salt
• What could Sample 1 be?
– Heterogeneous mixture  able to be filtered
• What could Sample 2 be?
– Homogeneous mixture  solid found to be
dissolved
Thinking question?!?
What would you classify NH4NO3 as? Explain
your reasoning.
– Compound
– Contains multiple capital letters, aka multiple
elements present
VI. Law of Conservation of Mass-Energy
(Matter)
You cannot create nor destroy matter or energy
in any physical or chemical change;
What you start with is always equal to what you
end with in any change;
The mass of the reactants will always equal the
mass of the products;
What has been here since “the beginning” is still
here, and will always be here until “the end;”
You can’t get something from nothing!