Mr. Fleming
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D.1 What are the effects adding energy to
matter in terms of the motion of atoms and
molecules, and the resulting phase
changes?
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There are four main
states of matter:
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Solid
Liquid
Gas
Plasma
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Solid- a substance with a
definite volume and
shape.
The particles are
vibrating in place, held in
place by attractions
between the particles.
Chemical and physical
properties of a substance
are determined by the
geometric pattern of the
molecules.
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Liquid- A substance with a
definite volume, but no
definite shape.
The particles in a liquid can
flow freely with in the
substance, but attractions
between the particles keep
them from escaping.
The liquid will take the
shape of its container.
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Gas- a substance
without a definite shape
or volume.
The particles in a gas
have very little
attraction for each other
and so they can move
about freely taking the
size and shape of their
container.
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Plasma- a high energy state of matter in
which atoms lose their electrons and exist as
electron free nuclei in a sea of electrons.
This requires temperatures greater than 1
million degrees Celsius.
Natural Plasmas exist as stars and can be
created for a brief time by very powerful
lightning bolts (1million + volts)
◦ Fluorescent and neon lights too
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Heating:
Adding heat to a substance causes its particles to
move faster. If there is enough energy they will
break the attractions holding them in that state
and move up to the next state.
Cooling:
Removing heat from a substance causes its
particles to slow down and allows the attractions to
begin to affect the particles drawing them together
into a lower state.
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During a phase change the temperature
remains constant, because the energy
changes are associated with making/breaking
attractions, not with particle movements.
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Melting Point- the temperature at which a
solid becomes a liquid.
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Freezing Point- liquid becomes a solid.
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Boiling Point- liquid becomes a gas.
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Triple Point- The temperature and pressure
at which the solid, liquid, and vapor phases of
a pure substance can coexist in equilibrium
Melting- a solid
becomes a liquid.
Freezinga liquid becomes a
solid.
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Vaporization- a
liquid becomes a
gas.
Condensation- a
gas becomes a
liquid.
Some materials can undergo a change in state
between the solid state and gaseous state
without becoming a liquid.
 Sublimation- a solid becomes a gas.
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Deposition- a gas becomes a solid.
Ionization- a phase change in which a gas
becomes plasma.
Deionization- a phase change in which plasma
becomes a gas.
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Was heat being added to the system during
the time that the temperature remained
relatively constant? How was the heat being
used during these temperature plateaus?
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During this experiment, heat was being
added to the system, but at times the
temperature remained relatively constant.
During this time the energy being added to
the system in the form of heat was being
used to break the bonds or attractions
between the molecules causing a phase
change.
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Was heat being added to the system during
the time the temperature was rising? How
was the heat being used at this time?
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During this experiment, heat was being
added to the system and the temperature of
the water was increasing. The energy being
added to the system in the form of heat was
increasing the kinetic energy, the motion of
the particles, making up the water.