Chemistry
Matter and Change
Chemistry is…
…the study of the
composition, structure,
and properties of matter
and the changes it
undergoes
C2H5OH + 3 O2  2 CO2 + 3 H2O + Energy
Reactants

Products
Matter
Anything that has mass and occupies space
Mass
A measure of the amount of matter
Atom
The smallest unit of an element that maintains
the properties of that element
Element
A pure substance made of only one kind of atom
Compound
A substance that is made from the atoms of two or
more elements that are chemically bonded.
Sucrose – C12H22O11
Sucrose is also known
as table sugar, and is
used to make Gummy
Bears!
Properties of Matter
Extensive properties depend on the amount
of matter that is present.
Volume
Mass
Energy Content (think Calories!)
Intensive properties do not depend on the
amount of matter present.
Melting point
Boiling point
Density
Physical Change
A change in a substance that does not involve a
change in the identity of the substance.
Example:
Phase Changes
Phase
Differences
Solid – definite volume and shape; particles packed
in fixed positions.
Liquid – definite volume but indefinite shape;
particles close together but not in fixed positions
Gas – neither definite volume nor definite shape;
particles are at great distances from one another
Plasma – high temperature, ionized phase of matter
as found on the sun.
Three Phases
Copper Phases - Solid
Copper Phases - Liquid
Copper Phases – Vapor (gas)
Chemical Change
A change in which one or more substances are
converted into different substances.
Heat and light are
often evidence of
a chemical change.
Classification of Matter
Separation of a Mixture
The constituents of the mixture retain their
identity and may be separated by physical
means.
Separation of a Mixture
The components of dyes
such as ink may be
separated by paper
chromatography.
Separation of a Mixture
Distillation
Separation of a Compound
The Electrolysis of water
Compounds must be
separated by chemical
means.
With the application of
electricity, water can
be separated into its
elements
Reactant

Water

H2O

Products
Hydrogen + Oxygen
H2
+
O2
Group or Family
Period
The Periodic Table
Group or
family
Period
Properties of Metals
 Metals are good
conductors of heat and
electricity
 Metals are malleable
 Metals are ductile
 Metals have high tensile
strength
 Metals have luster
Examples of Metals
Potassium, K
reacts with
water and
must be
stored in
kerosene
Copper, Cu, is a relatively soft
metal, and a very good electrical
conductor.
Zinc, Zn, is
more stable
than potassium
Mercury, Hg, is the only
metal that exists as a
liquid at room temperature
Properties of Nonmetals
Carbon, the graphite in “pencil lead” is a great
example of a nonmetallic element.
 Nonmetals are poor conductors of heat and
electricity
 Nonmetals tend to be brittle
 Many nonmetals are gases at room
temperature
Examples of Nonmetals
Sulfur, S, was
once known as
“brimstone”
Graphite is not the only
pure form of carbon, C.
Diamond is also carbon;
the color comes from
impurities caught within
the crystal structure
Microspheres
of phosphorus,
P, a reactive
nonmetal
Properties of Metalloids
Metalloids straddle the
border between metals
and nonmetals on the
periodic table.
 They have properties of both metals and
nonmetals.
Metalloids are more brittle than metals, less
brittle than most nonmetallic solids
 Metalloids are semiconductors of electricity
 Some metalloids possess metallic luster
Silicon, Si – A Metalloid
 Silicon has metallic luster
 Silicon is brittle like a nonmetal
 Silicon is a semiconductor of
electricity
Other metalloids include:





Boron, B
Germanium, Ge
Arsenic, As
Antimony, Sb
Tellurium, Te