CHEM 1

• Every particles of matter are in constant random motion, that according to the kinetic molecular theory or model
• All particles of matter regardless of the state (solid, liquid, and gas) posse's kinetic energy, KE
• Average kinetic energy


  Related to the particles' average speed, is proportional to the absolute temperature
• In terms of order, gas tends to be more disordered than the liquid and solid
• Solid particles are vibrating and the frequency of it cannot be notice by the naked eye
• Assumptions in Kinetic Molecular Model


  • Particles are in constant, random straight motion
  • Volume of individual particles is zero and are separated by great distances
  • Particles can collide to the wall or to each other very rapidly and elastic
  • No forces exist between particles
  • Total energy remains constant
• The assumptions behind the kinetic molecular theory can be illustrated with the apparatus shown in the figure below, which consists of a glass plate surrounded by walls mounted on top of three vibrating motors. A handful of steel ball bearings are placed on top of the glass plate to represent the gas particles
• Fluids


  Gases and liquids have the ability to flow
• Gases and liquids have intermolecular forces of attraction that can affect their properties
• London dispersion force


  The intermolecular force primarily responsible for the condensed states of nonpolar substances
• Dipole-dipole forces


  Intermolecular forces
• Hydrogen bond


  The partially positive H of one molecule is attracted to the partially negative lone pair on the N, O, or F of another molecule
• Ion-dipole forces


  The attractions between the ions and the oppositely charged poles of the H2O molecules overcome the attractions between the ions themselves
• Surface tension


  Liquids that have strong intermolecular forces also have high surface tension
• Viscosity


  Property of liquids
• Vapor pressure


  Property of liquids
• Boiling point


  Property of liquids
• Molar heat of vaporization


  Property of liquids
• Crystalline solids


  Type of solid
• Amorphous solids


  Type of solid
• Applications of amorphous solids

  • Many applications, some examples not provided