Science— particular of matter

• Diffusion


  The movement of particles from an area of high concentration to an area of low concentration
• Diffusion in gas


  1. Bromine gas diffuses upwards

  2. Air particles diffuse downwards

  3. Particles mix completely and are evenly distributed
• Temperature


  Affects the rate of diffusion
• Higher temperature


  Particles gain more kinetic energy and move around at higher speed
• States of matter


  • Solid: fixed shape, fixed volume, cannot be compressed
  • Liquid: no fixed shape, fixed volume, cannot be compressed
  • Gas: no fixed shape, no fixed volume, can be compressed
• Particle arrangement


  • Solid: very closely packed in fixed positions
  • Liquid: slide past one another, can roll and move randomly
  • Gas: a lot of empty space between, move quickly in any direction
• Particle forces


  • Solid: very strong forces
  • Liquid: less strong forces, enough to keep particles together
  • Gas: very weak, negligible forces
• Heating from A to B

  1. Particles gain heat energy which is converted to kinetic energy

  2. Particles begin vibrating more
• Melting from B to C

  1. Temperature remains constant

  2. Particles gain heat energy which weakens attractive forces between them