Pressure
n
Determined by the number of collisions between
the particles of a gas and their container
n
force exerted per
unit of area
n
Measured in pascals (pa)
To analyze the behavior of a gas:
1. Pressure (P)
Related to
the number of collisions
2. Temperature (T)
Related to
the speed of the particles
3. Volume (V)
The amount
of space a gas occupies
4. Mass (M)
Related to
the number of gas particles
(Usually expressed in moles of gas)
The
pressure and volume of a sample of gas at constant temperature are inversely
proportional to each other
P1V1 = P2V2
At
constant pressure, the volume of a fixed amount of gas is directly proportional
to its absolute temperature
V1 = V2
T1 T2
P1V1 = P2V2
T1 T2
nAll matter is made of tiny particles that are in constant
motion.
nThe rate of motion determines temperature and state of
matter.
Be able to describe states of
matter including solid, liquid, gas and plasma
Plasma
n
The fourth state of matter.
n
High energy, electrically charged form of matter.
n
When the temperature of a sample is increased,
its electrons can gain so much energy that they separate from their
nuclei. This forms a plasma.
n
The surface of the sun is a plasma. You create a plasma inside a fluorescent
lamp whenever you turn it on.
Thermal Expansion
n
When matter is heated, it tends to expand.
n
Added heat is converted into kinetic energy of
the particles… the particles move faster and farther apart…the chunk of matter
expands.
n
The particles do not expand, the piece of matter
does!
Phase Changes – Changes of State
n
Adding or removing energy (heat) to a substance
causes phase changes
n
During a phase change, temperature does NOT
change
Phase changes
n
Melting S Δ L
n
Boiling L Δ G
n
Freezing L Δ S
n
Condensation G Δ L
n
Evaporation L Δ G
n
Deposition G Δ S
n
Sublimation S Δ G
Be able to describe where each of
the above Phase changes occur on a heating or cooling curve. Be able to explain what happens to KE and PE
during each segment of the heating/cooling curve.
Heat
of Fusion
-amount
of energy required to change solid to a liquid, and a liquid to a solid
Heat
of Vaporization
-amount
of energy required to change a liquid to a gas and a gas to a liquid