MATTER
Chapter 3
Section 3.1
The Particulate Nature of Matter
Objective:

Learn about the composition of matter
Matter
Matter is anything that:


a) has mass, and
b) takes up space
Mass = a measure of the amount of
“stuff” (or material) the object contains
(don’t confuse this with weight, a
measure of gravity)
Volume = a measure of the space
occupied by the object
States of Matter
Objective:

To define the 3 states of matter
States of matter
1) Solid- matter that can not flow (definite
shape) and has definite volume.
2) Liquid- definite volume but takes the
shape of its container (flows).
3) Gas- a substance without definite volume
or shape and can flow.
*
Vapor- a substance that is currently a gas,
but normally is a liquid or solid at room
temperature. (Which is correct: “water gas”,
or “water vapor”?)
States of Matter
Definite Definite
Volume? Shape?
Solid
Liquid
Gas
YES
YES
NO
Result of a
TemperatureI Will it
Compress?
ncrease?
YES
Small
Expands.
NO
NO
Small
Expands.
NO
NO
Large
Expands.
YES
Three Main Phases
Solids – molecule are locked into fixed positions….little movement to move
Liquids – molecules can slide past one another
Gas – a free to move randomly about
Copper Phases - Solid
Copper Phases - Liquid
Copper Phases – Vapor (gas)
Condense
Freeze
Evaporate
Melt
Solid
Liquid
Gas
4th state: Plasma - formed at
high temperatures; ionized phase
of matter as found in the sun
Ever heard of a Bose-Einstein
Condensate???
http://www.pbs.org/wgbh/nova/physics/ultr
acold-atoms.html
Section 3.2
Physical/Chemical Properties and Changes
Objective:


To distinguish between physical and chemical
properties
To distinguish between physical and chemical
changes
Properties are…
Words that describe matter (adjectives)
Physical Properties- a property that can be
observed and measured without changing
the material’s composition.
Describes individual characteristics
Examples- color, hardness, m.p., b.p.
Chemical Properties- a property that can
only be observed by changing the
composition of the material.
Describes social characteristics
Examples- ability to burn, decompose,
ferment, react with, etc.
Physical vs. Chemical Change
Physical change will change the visible
appearance, without changing the
composition of the material.


Boil, melt, cut, bend, split, crack
Is boiled water still water?
Can be reversible, or irreversible
Chemical change - a change where a
new form of matter is formed.

Rust, burn, decompose, ferment
Recognizing Chemical Changes
1) Energy is absorbed or released
(temperature changes hotter or colder)
2) Color changes
3) Gas production (bubbling, fizzing, or odor
change; smoke)
4) formation of a precipitate - a solid that
separates from solution (won’t dissolve)
5) Irreversibility - not easily reversed
But, there are examples of these that are not
chemical – boiling water bubbles, etc.
Section 3.5
Separation of Mixtures
Objective:

Learn 2 methods of separating a mixture
Separation of a Mixture
Objective:

Learn 2 methods of separating mixtures
Separating Mixtures(talk more about mixtures is tomorrow)
Some mixtures can be separated
easily by physical means: rocks and
marbles, iron filings and sulfur (use
magnet)
Differences in physical properties
can be used to separate mixtures.
Filtration - separates a solid from
the liquid in a heterogeneous
mixture (by size) – Figure 2.7, page 46
Filtration
separates a
liquid from a
solid.
Separation of a Mixture
Distillation: takes advantage of different boiling points.
NaCl boils at 1415 oC
Another view of
Distillation
Separation of a sand-saltwater mixture
To separate sand-saltwater mixture:
first use filtration to separate sand from saltwater
then use distillation to separate salt and water
Section 3.3
Elements and Compounds
Objective:

The difference between a element & compound
What about atoms?
All matter is made up of
tiny particles called
ATOMS
Although objects look
quite continuous and
uniform, they are really
particulate in nature
Atoms are not all alike
About 100 different types
of atoms make up all the
different types of matter

Think of the alphabet
(atoms) and words (matter)
Element, Compound or Molecule
Elements simplest kind of matter
 cannot be broken down any simpler and still have
properties of that element!
 all one kind of atom.
Compounds are substances that can be broken down
only by chemical methods
 when broken down, the pieces have completely
different properties than the original compound.
 made of two or more different atoms, chemically
combined (not just a physical blend!)
Molecules are substances that can be broken down only
by chemical methods

made of two or more atoms, chemically combined
(not just a physical blend!)
I am not clear on what a molecule is. If water is a molecule, is it also a
compound because the hydrogen and oxygen have been chemically
combined? If so, how do you determine whether a substance is a compound
or a molecule?
A molecule is what you get when any atoms join
together.
A compound is what you get when atoms of two or more
different elements join together.
All compounds are molecules, but not all molecules are
compounds.
Water is a molecule because it is made from atoms that
have been chemically combined. It is also a compound
because the atoms that make water are not all the same
- some are oxygen and some are hydrogen.
Oxygen in the atmosphere is a molecule because it is
made from two atoms of oxygen. It is not a compound
because it is made from atoms of only one element oxygen. This type of molecule is called a diatomic
molecule, a molecule made from two atoms of the same
type.
Elements vs Compounds
Currently, there are 117 elements
Elements have a 1 or two letter symbol,
and compounds have a formula.
An element’s first letter always capitalized;
if there is a second letter, it is written
lowercase: B, Ba, C, Ca, H, He
Some names come from Latin or other
languages
Compounds vs Elements
Compounds can be broken down into
simpler substances by chemical means,
but elements cannot.
Compounds always contain atoms of
different elements…..Always in the same
composition
 Ex. Water is always found as 2
hydrogen atoms combined with 1
oxygen atom
Section 3.4
Mixtures vs Pure substance
Objective:

To distinguish between mixtures and pure
substances
Mixtures
Mixtures - are a physical blend of at
least two substances; have variable
composition. They can be either:
1) Heterogeneous – the mixture different
it is not uniform in composition
• Chocolate chip cookie, gravel, soil.
2.) Homogeneous - same composition
throughout; called “solutions”
• Kool-aid, air, salt water
Every part keeps it’s own properties.
Solutions are homogeneous mixtures
Mixed molecule by molecule, thus too
small to see the different parts
Can occur between any state of
matter: gas in gas; liquid in gas; gas
in liquid; solid in liquid; solid in solid
(alloys), etc.
Thus, based on the distribution of
their components, mixtures are called
homogeneous or heterogeneous.
Alloy – mixture of metals
Twenty-four-karat gold is an element
Eighteen-karat gold is an alloy.
Fourteen-karat gold is an alloy.
*An alloy is a mixture or metallic solid solution
composed of two or more elements
Tie together some of the
information
What is the difference then
between a mixture and a
compound????
Compound vs. Mixture
Compound
Mixture
Made of one kind
of material
Made of more than
one kind of material
Made by a
chemical change
Made by a
physical change
Definite
composition
Variable
composition
Pure Substances
Pure substances – always have same
composition

Either elements or compounds
Ex pure water is a pure substance – it only
contains H2O molecules
Tap water is a mixture – it contains H2O and other
minerals such as calcium and magnesium
Classification of Matter
Which is it?
Element
Which is it?
Compound/molecule
Which is it?
Mixture
Which is it?
Molecule.
CANNOT be a compound.
WHY????
Chapter 3
The End
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Chapter 2