States of Matter Unit
Learning Target
Notes
Section 1: Matter and Energy
Matter is made of atoms and molecules that are in
constant motion.
Kinetic Theory of Matter
A. Particles that make up matter are in
constant motion.
B. The higher the temperature, the faster the
particles move.
C. At the same temperature, more massive
particles move slower than less massive
particles.
What is the difference between a solid, a liquid,
Solid – has definite shape and volume
and a gas?
Liquid – has definite volume, but not definite
shape
Gas – changes both volume and shape
What makes up matter?
The difference between a solid, a liquid, and a gas
is solids and liquids don’t change volume, but
gases do.
What kind of energy do all particles of matter
have?
Plasma – no definite volume or shape; electrically
charged state of matter (ionized); examples:
lightning, fire, the Sun…
KINETIC ENERGY
Temperature is a measure of average kinetic
energy.
Thermal energy – TOTAL kinetic energy;
dependent on particle speed and number of
particles.
States of Matter Unit
Section 2: Changes of State
What happens when a substance changes from
The identity of the substance doesn’t change, but
one state of matter to another?
the energy of the substance does change.
Freezing – Energy is released
(liquid -> solid)
Melting – Energy is absorbed
(solid -> liquid)
Condensation – Energy is released (gas -> liquid)
Vaporization – Energy is absorbed (liquid -> gas)
Sublimation – Energy is absorbed (solid -> gas)
Deposition – Energy is released
(gas -> solid)
Temperature is constant during change of state.
What happens to mass and energy during physical
and chemical changes?
**You need to know the diagram at the bottom of
page 84
Mass and energy are both conserved.
NEITHER MASS OR ENERGY CAN
BE CREATED OR DESTROYED!
Law of Conservation of Mass
Law of Conservation of Energy
States of Matter Unit
Section 3: Fluids
How do fluids exert pressure?
Pressure – the amount of force exerted per unit
area of a surface
FLUID (Chapter 2): a nonsolid state of matter in
Fluids exert pressure evenly in all directions.
which the atoms or molecules are free to move
past one another, as in a liquid or a gas.
P = F/A (Pressure = Force divided by Area)
SI unit: pascal (1 N/m2)
What is buoyant force?
All fluids exert an upward buoyant force on
matter.
-The upward force that keeps an object immersed
in or floating on a liquid.
Archimedes’ Principle
The buoyant force on an object in a fluid is an
upward force equal to the weight of the fluid that
the object displaces.
What happens when pressure in a fluid changes?
An object will float or sink based on its density
and surface area.
Pascal’s Principle
A change in pressure at any point in an enclosed
fluid will be transmitted equally to all parts of the
fluid.
𝑃1 = 𝑃2
𝐹1 𝐹2
=
𝐴1 𝐴2
What affects the speed of a fluid in motion?
(Hydraulic devices are based on Pascal’s Principle.)
Fluids move faster through small areas than
through larger areas, if the overall flow rate
remains constant. Fluids also vary in the rate at
which they flow.
Viscosity – the resistance of a gas or liquid to flow
 Dependent on particle attraction
 The more attracted the particles are the
slower (more viscous) a fluid is. (Ex:
Honey)
Fluid pressure decreases as speed increases.
 Bernoulli’s Principle – as the speed of a
moving fluid increases, the pressure of the
moving fluid decreases
States of Matter Unit
Section 4: Behavior of Gases
What are some properties of gases?
Gases expand to fill their containers.
They spread out easily and mix with one another.
They have low densities and are compressible.
They are mostly empty space.
Gases exert pressure on their containers.
How can you predict the effects of pressure,
GAS LAWS
temperature, and volume changes on gases?
1. Boyle’s Law – relates pressure to volume
At constant temperature, the volume of a
gas increases as the gas’s pressure
decreases. If the volume decreases, the
pressure increases.
Inverse relationship – curved graph
2. Gay-Lussac’s Law – relates pressure to
temperature
Pressure of a gas increases as the
temperature increases. The pressure
decreases as the temperature decreases.
Direct relationship – straight-line graph
3. Charles’s Law – relates temperature to
volume
At a constant pressure, volume of a gas
increases as the temperature increases. If
the volume decreases, the temperature
decreases.
Mathematical Formulas of Gas Laws
Direct relationship – straight-line graph
Boyle’s Law 𝑃1 𝑉1 = 𝑃2 𝑉2
Gay-Lussac’s Law
Charles’s Law
The Ideal Gas Law
Conversions
K = °C + 273
3
1 cm = 1 mL
3
1 dm = 1 L = 1000 mL
Standard Conditions
0°C = 273 K
1 atm = 760 mm Hg = 101.325 kPa = 101,325 Pa
𝑉1
𝑇1
𝑃1
𝑇1
=
𝑃2
𝑇2
𝑉
= 𝑇2
2
The ideal gas law relates the variables of pressure, volume,
temperature, and number of moles of gas within a closed
system.
PV = nRT
P = pressure of the confined gas (unit: atm)
V = volume of the confined gas (unit: L)
n = number of moles of gas
R = gas constant (0.0821 L atm/mol K)
T = temperature (unit: K)
States of Matter Unit