1.1 particle model

• Particle model


  A model that describes the properties of materials in terms of tiny particles
• The rock of the mountains is a material
• All materials are made up of tiny particles
• Particles are too small to see
• Substance


  A material that has one type of matter
• Mixture


  A material that is made up of more than one type of matter
• Most materials are mixtures
• Wood is a mixture
• Soil and most rock are mixtures
• Substances include silver, sugar, and pure water
• All the particles in a substance are the same as each other
• Particles of different substances are different
• Every substance has its own type of particle
• Properties


  What a substance is like and what it does
• Every substance has its own properties
• Particle model


  Describes the arrangement and movement of the particles in a substance
• Particle model


  • Can be used to explain properties of a substance
  • Properties depend on: what its particles are like, how its particles are arranged, how its particles move, how far apart the particles are, how strongly its particles hold together
• Gold particle


  • Similar size to a copper particle
  • But a gold particle is heavier than a copper particle
• Gold coin and copper coin of the same size

  Gold coin is heavier than copper coin
• Liquid water and steam


  • Have the same particles
  • But the particles in steam are further apart than the particles in liquid water
• One gram of steam


  Takes up more space than one gram of liquid water
• Liquid water


  • Particles move around
• Solid rock


  • Particles held in one place
• Liquid water


  Flows
• Solid rock


  Does not flow
• Silver


  • Particles hold together less strongly than the particles in diamond
• Silver


  Easier to scratch than diamond