Changes of state and particle model

• What’s the definition of density

  The mass per unit volume of a material
• Density equation

  Density= mass/ volume
• State the different states of matter in order of density

  • Least dense :gas
  • liquid
  • most dense : solid
• Describe the particle arrangement of a solid

  Tightly packed in a regular arrangement with the particles only being able to vibrate on the spot
• Describe the particle arrangement of a liquid

  Close together, but with an irregular arrangement. They can flow over each other
• Describe the particle arrangement of a gas

  Separated, with no regular arrangement. particles can move freely
• What is always conserved when a substance undergoes a change of state

  Mass
• How does a change of state differ from a chemical change

  In a change of state the material can return to having its previous properties if the change is reversed
• What is sublimation

  When a solid changes into a gas without passing through a liquid state
• What is evaporation

  When a liquid changes into a gas state
• What’s the opposite of evaporation

  Condensation, which is where a gas changes into a liquid state