1. STATES OF MATTER
Chemistry CP

2. Energy
Potential Energy: Stored Energy If you heat a substance, that substance will store some of that energy in its particles Kinetic Energy: Energy of Motion

3. Kinetic Energy: Increases in kinetic energy result in increases in temperature
Heat added to a system that is not stored as potential energy will be absorbed by the particles which will increase the particles’ kinetic energy
Absolute Zero (0 K): The temperature at which the motion of particles theoretically ceases and the particles have no kinetic energy

4. Directly proportional to the kinetic energy of the particles
Kelvin Scale: Reflects the relationship between temperature and average kinetic energy
Directly proportional to the kinetic energy of the particles
K = C + 273

5. All matter consists of tiny particles that are in constant motion
Kinetic Theory
All matter consists of tiny particles that are in constant motion

6. Intermolecular Forces
Hydrogen Bonding: The large partial charge resulting in an extremely strong dipole-dipole force between hydrogen of on molecule (+) and the F, O or N of another molecule (-)
One of the strongest intermolecular forces
Dipole-Dipole Forces: Attractions between opposite charges of neighboring permanent dipoles
Happens between polar molecules
Dispersion Forces: A force of attraction between induced dipoles
Induced dipoles occur when a temporary dipole occurs (the e- move to one side of an atom simply through their natural movement)
Can happen between nonpolar molecules
Strength

8. SOLID
LIQUID
GAS
Ionic, Metallic or Molecular Bonds (Strong Bonds between atoms)
Atoms, ions or molecules are packed tightly together
Particles vibrate around fixed points
Crystalline or Amorphous Solids
Do not flow
Condensed state of matter (pressure has little effect on a solid)
Only slightly compressible
High density
Extremely slow diffusion (only occurs at surface)
Definite volume
Definite shape
Molecules or Atoms
Intermolecular forces keep the particles in a liquid close together
Intermolecular forces reduce the amount of space between the particles
Condensed state of matter (pressure has little effect on a liquid)
Can flow (a fluid)
Does not expand to fill the container
Assumes the shape of the container
Slow diffusion
No definite shape
Particles are small, hard spheres with insignificant volume
Particles are far apart with empty space between them
No attractive or repulsive forces between particles
Motion of one particle is independent of the rest
Motion of particles is rapid, constant and in straight line paths until they collide
Perfectly elastic collisions (kinetic energy remains constant)
Can be compressed
Low density
Fills container completely
Assumes shape of container
Rapid Diffusion
No definite volume nor shape

9. Vacuum: An empty space with no particles and no pressure
Gas Pressure: The force exerted by a gas per unit surface area of an object
Caused by the collisions of the moving gas particles with an object
Barometer: Device that is used to measure atmospheric pressure
Atmospheric Pressure: Results from the collisions of atoms and molecules in air with objects
Gasses

11. Units of Pressure 1 atm = 760 mm Hg = 101.3 kPa
Pascal (Pa): SI unit of pressure
atmosphere: Pressure required to support 760 mm Hg in a mercury barometer at 25C
mm Hg: Unit on a barometer
Standard Temperature & Pressure (STP): Temperature of 0C and 1 atm

12. LIQUIDS Vapor Pressure: A measure of the force exerted by a gas
above a liquid
At equilibrium: The rate of evaporation of the liquid equals the rate of condensation of the vapor

13. MANOMETER: Measures the vapor pressure of a contained liquid

14. Affect of Temperature on Vapor Pressure
An increase in temperature of a contained liquid will increase the vapor pressure because the kinetic energy will increase resulting in more particles escaping the surface of the liquid.

15. VISCOSITY A liquids resistance to motion
Liquids with stronger intermolecular forces will have higher viscosities
Water’s viscosity is relatively high due to its hydrogen bonding
Lower temperatures = higher viscosity

16. Greater in liquids with strong intermolecular forces
SURFACE TENSION
Imbalance of attractive forces at the surface of a liquid that causes the surface to behave as if it had a thin film across it
Greater in liquids with strong intermolecular forces

17. SOLIDS
Crystals: The particles are arranged in an orderly, repeating, 3-dimensional pattern called a crystal lattice
The shape of the crystal reflects the arrangement of the particles within the solid
Unit Cell: The smallest group of particles within a crystal that retains the geometric shape of the crystal

18. SOLIDS Amorphous Solids: Lacks an ordered internal structure
Plastic, rubber, glass, asphalt

19. Change of State Conversion of a substance from one of
three physical states of matter to
another.
A.k.a: Phase Change
Always involves: A change in energy

20. Energy & State Changes
Gases have the most potential energy, solids the least

21. VAPORIZATION: The change of state from a liquid to a gas
Evaporation: Molecules at the surface of a liquid escape and enter the gas phase
Boiling: When the vapor pressure of the liquid is equal to the atmospheric pressure, bubbles of gas form and escape the liquid.
Evaporation rates increases with increases in temperature because the increase in energy allows more molecules to escape the surface of the liquid
The molecules remaining behind in the liquid are lower in energy
Boiling Point: The temperature at which the vapor pressure of the liquid becomes equal to the atmospheric pressure
Normal Boiling Point: The boiling point of a liquid at a pressure of kPa (normal atmospheric pressure)

22. If atmospheric pressure increases, the temperature needed to reach the boiling point will also increase. If atmospheric pressure decreases, the temperature needed to reach the boiling point will also decrease.

23. CONDENSATION
The change of state from a gas to a liquid

24. FREEZING The change of state from a liquid to a solid.
Freezing Point: The
temperature at
which the solid
and liquid forms of
a substance exist
in equilibrium

25. MELTING The change of state from a solid to a liquid
Melting Point: The temperature at which a solid changes into a liquid
Equals: The freezing point

26. Sublimation: The change of state from a solid to a gas
Deposition: The change of state from a gas to a solid
Typically occurs with molecular solids with weak intermolecular forces.

28. HEATING CURVE
During a state change, the temperature remains constant while the potential energy increases/decreases. This will occur until the state is completely changed and then kinetic energy will begin to increase/decrease again.

29. Phase Diagram
Relates the state of a substance to its temperature and pressure.
Triple Point: The only set of conditions at which all three phases can exist in equilibrium with one another
For water, the triple point is 0.016C and 0.61 kPa/ atm