Particle model

• Particle model


  Made from particles (small, inelastic spheres)
• States of matter


  • Solids
  • Liquids
  • Gases
• Particles


  • Can be drawn as circles
• Arrangement of particles in different states of matter

  1. Solids: Fixed position, vibrate only

  2. Liquids: Close but can move past each other, irregular arrangement

  3. Gases: Free to move randomly at high speeds, irregular arrangement
• As particles gain kinetic energy


  Forces of attraction weaken
• As particles gain kinetic energy


  Particles move faster
• As particles gain kinetic energy


  Density decreases
• As particles gain kinetic energy


  Particles can overcome forces holding them together and change state
• Solids have the highest density as particles are closest together
• Liquids are less dense than solids
• Gases have the lowest density
• Liquids can flow to fit a container
• Gases can expand to fill a container or increase pressure in a fixed container
• Cooling a gas down reduces the kinetic energy of particles, allowing bonds to form and the gas to condense into a liquid
• Heating a solid provides enough energy for particles to overcome the forces holding them together, causing the solid to melt into a liquid