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Properities of solids liquids and gases
Phases: States of matter and the changes they undergo
Liquids: Definite volume
takes the shape of its container
particles are in constant motion
Intermolecular forces
1. Dipole-dipole (positives and negatives attract) polar substances
2. London dispersion forces (temporary dipole positives and negatives attract)
   Nonpolar substances
3. Hydrogen bonding (positives hydrogen atom attracts to the more electronegative element    
   Of the neighboring molecule) polar substances
Less compressible than gases due to close arrangement of the particles
Ability to diffuse
Surface Tension
    1.  Capillary action
Evaporation and Boiling
Heating / Melting curve
1.  Vaporization: the process by which a liquid or a solid changes to a gas
Evaporation: particles escape from the surface of a nonboiling liquid and enter the gas State.
3.  Boiling: internal pressure equals the external pressure
Freezing point is the change of a liquid to solid by removing heat.   f.p. is the same temperature as melting point temperature.
Solids: Definite shape and volume molecules vibrating around a fixed point -strong intermolecular forces.
   Intermolecular forces and fixed position
*Types of solids:
*Crystal structure (ionic)
*Ionic- unit cell (metal and nonmetal)
*Covalent (2 or more nonmetals)
*Metallic (sea of electrons)
*Covalent molecular  
*Amorphous
    *Molar heat of fusion: the amount of energy needed to melt 1 mole of a substance.
sH fus = 6.01 KJ/mol
The higher the heat of fusion the stronger the intermolecular forces
    *Definite Melting Point
Melting: converts from solid to liquid
Melting point same as freezing point
    *Molar heat of vaporization the amount of heat energy needed to vaporize1mol of a substance at its bp. gas.
sH vap =  40.7  KJ/mol
The higher the heat of vaporization the stronger the intermolecular forces.
*Supercooled liquids: Glass
Nonpolar: Electrons are shared evenly weak London dispersion forces
Ex:
Polar: Electrons are shared unevenly. Due to dispersion forces, dipole-dipole, hydrogen bonding
     Ex:
Changes of State:
Equilibrium Equation
(Heating) liquid + heat energy = vapor    Endothermic
   Heat absorbed
   temperature falls
   posiive enthalphy change
   breaking of bonds

(Cooling) vapor = liquid + energy            Exothermic
   heat is released
   temperature rises
   negative enthalpy change
   bond formation
Le Chatelier's Principle
      When a system at equilibrium is disturbed by application of a stress, it attains a new equilibrium position that lowers the stress.
Effects of temperature
    Temperature ­ products favored
    Temperature ¯ reactants are favored

Effects of concentration
    Liquid  ­ products favored    Liquid ¯  reactants favored
    Vapor ­  reactants favored    Vapor ¯  products favored

Effects of pressure
    Pressure­products favored    Pressure  ¯ reactants favored

Vapor pressure
    The pressure a liquid applies to the atmosphere to become a vapor
   Vapor pressure increases when temperature goes up (directly proportional)
   Vapor pressure decease's when vapor pressure goes down (indirectly proportional)
    Volatile:  Liquid turns to a gas easily   ex: alcohol
   Nonvolatile:  Liquid does not turn to a gas easily   ex: oil

Know how to interpret the vapor table


   
   Phase change diagram
Points to know: Triple point, Normal fp ,Normal bp, Critical point
Areas to know:  solid, liquid, gas