Matter
Matter- What is it?
 Matter: Anything with mass and volume
Ex. Peanut Butter, Pencils, Chairs, Cars, Wind
Not Matter: Beam of Light, Shadow, Reflection
(because none of those things contain mass)
 Volume: Amount of space an object occupies
 Mass: Amount of stuff in an object, not gravity
dependent
 Weight: Depends on gravity
Mass vs. Weight
Properties of Matter — Physical
 Do not change the chemical composition
of the matter
 Used to ID a substance
 Examples: state (solid, liquid, or gas), boiling
and melting point, texture, mass, color, shape,
density, odor, volume, size, malleable, ductile.
Physical Properties can be divided into
2 groups:
 Extensive: Depends
on the amount of the
substance
 Intensive: Does
NOT depend on
the amount of
 Examples: Mass and
Volume,
the substance
 Examples: Color,
Texture, State,
Density (Density
is the ratio of the
mass of an object
to its volume)
Shape,
Size
Physical Properties
The Four States of Matter
 Solid: Fixed volume and shape
(Lowest kinetic energy-energy of motion)
 Liquid: Fixed volume and indefinite
shape (Takes the shape of container)
 Gas: Indefinite volume and shape
(Fills the container) Highest kinetic energy
 Plasma: A high temperature state of matter
in which atoms lose their electrons.
(Happens in a fluorescent light bulb and stars,
like our sun)
States of Matter
Particle Model of Water
Physical Changes (Cont.)
 Physical Changes are
 If a substance goes from a
reversible or irreversible. liquid to a solid this is a
They do NOT affect
reversible physical change
chemical composition!
since it can melt back.
 Example: Change of
 Crushing a rock is an
state (boil, freeze, melt,
irreversible physical change
condense) cut, crush,
because the rock does not
break, and dissolving.
go back together.
Water to ice is a reversible
physical change.
Physical Change
Endothermic Changes
Endothermic changes: Energy is absorbed
thereby increasing the internal energy of
the molecules. It goes from low energy to
higher energy. (Can feel cool to touch)
Examples: Solid to Liquid (low to higher
energy) or Liquid to Gas (lower to higher)
Ice melting; Boiling water; CO2 cartridge
feels cold.
Exothermic Changes
Exothermic changes: Energy is given off
thereby decreasing the internal energy of
the molecules. It goes from high energy to
lower energy. (Can feel warm to touch)
Examples: Liquid to Solid (higher to low
energy) or Gas to Liquid (high to lower)
Water freezing to ice or steam condensing
to form water; hand warmers giving off
heat (warm to touch)
Changes of State Models for Water
Chemical Properties
 How matter reacts when it comes in contact
with other substances
 Examples: Reactivity—Lithium in water
smokes, Potassium in water flames,
Cesium in water explodes.
Potassium in water
Chemical Changes
 Alter the chemical composition
of one or more substances. A
chemical reaction is a change
that produces matter with a
different chemical composition
than the original matter.
 All chemical changes are
accompanied by transfers of
energy.
 Ex. Burn, rot, rust, explode,
decompose, baking, cooking.
Chemical Change
Three States of Sodium
Sodium metal going to a gas is what type of
reaction?
Endothermic and Physical change!
Baking bread is what type of reaction?
Endothermic and
Chemical Change!
Evidence of a Chemical Change
Evolution
of a gas
Evidence of a Chemical Change
Formation of a
precipitate.
When a solid forms
from mixing 2 liquids.
Evidence of a Chemical Change
Formation of heat or light
as energy is given off, or
feeling cold to the touch as
energy is absorbed (An
exchange of energy)
Evidence of a Chemical Change
Color change (Not always an
indicator, such as food
coloring in water).