Kinetic theory

• In solids, the particles vibrate around fixed positions
• In a solid:

  • particles are closely packed
  • Incompressible
  • Vibrate in fixed positions
  • Cannot be mixed
• In a liquid:

  • particles are slightly spread apart
  • Some freedom
  • Random movement
  • Particles take the shape of the container
• In a gas:

  • particles have complete freedom
  • vibrate in random positions
  • Expand the container
  • Compressible
• Temperature = average kinetic energy per molecule
• during cooling, the particles vibrate less so they lose kinetic energy
• what do we call when particles individually gain kinetic energy on a microscopic scale?

  total kinetic energy of all particles and internal energy
• during heating, the particles vibrate more and gain kinetic energy
• temperature is measure of how intense the heat is (average kinetic energy) measured in degrees celsius or kelvin (K)
• incompressible - cannot be dqueezed
• intermolecular forces between solids are stronger and less withing liquids and gases