Kinetic theory

Cards (17)

  • Diffusion
    Particles spread out from where they are in high concentrations to where they are in low concentrations
  • Diffusion is evidence that something spreads out – this something is a particle
  • Coloured compounds can be diluted many times before the colour disappears, which is evidence that particles must be very small
  • States of matter
    • Solids
    • Liquids
    • Gases
  • A substance can usually exist in all three states, dependent on temperature (and pressure)
  • Melting
    SolidLiquid (when heating up)
  • Freezing
    LiquidSolid (when cooling down)
  • Boiling
    LiquidGas (when heating up)
  • Condensing
    GasLiquid (when cooling down)
  • Solid
    • Close arrangement, Ordered, Vibrate around fixed positions
  • Liquid
    • Close arrangement, Random, Move freely past each other
  • Gas
    • Far apart arrangement, Random, Move completely freely
  • Melting of a solid
    Particles gain kinetic energy, moving faster, until they have enough energy to overcome the forces holding them together and start to move past each other forming a liquid
  • Boiling of a gas
    Particles lose kinetic energy, moving more slowly, forces of attraction start to form between the particles, the forces start to hold the particles together as a liquid
  • Ammonium Chloride Tube
    • Two gases, ammonia and hydrogen chloride, diffuse from the ends of the sealed tube, where they meet the compound ammonium chloride forms as a white smoke
  • The hydrogen chloride molecules must be heavier, as they diffused slower
  • If you heat up the tube
    The white smoke forms faster because the particles move faster and collide more often