States of matter

• What are the three states of matter?

  Solid, liquid, and gas
• What does particle theory help explain?

  How particles behave in different states
• How are particles modeled in particle theory?

  As small solid inelastic spheres
• What holds particles together in solids?

  Strong forces of attraction
• What structure do particles form in solids?

  A regular lattice structure
• Why do solids have a definite shape and volume?

  Particles are fixed in position
• How do particles in solids behave?

  They vibrate in their fixed positions
• What happens to solid particles when heated?

  They gain energy and vibrate more
• What is the temperature at which a solid melts called?

  Melting point
• What occurs at the melting point?

  Particles break free from their bonds
• How are particles arranged in liquids?

  Randomly, but fairly compact
• What allows liquids to flow?

  Weak forces of attraction between particles
• What happens to liquid particles when heated?

  They gain energy and move faster
• What is the temperature at which a liquid boils called?

  Boiling point
• What occurs at the boiling point?

  Particles break bonds and evaporate
• How do gas particles behave?

  They move freely and randomly
• Why do gases not have a definite shape or volume?

  Particles fill the container they are in
• What does random motion of gas particles mean?

  Particles can travel in any direction
• What happens when gas particles are heated?

  They gain energy and travel faster
• What happens to gas in an expandable container when heated?

  The gas expands
• What happens to gas in a fixed container when heated?

  The pressure increases
• What happens when gas is cooled down?

  Particles form bonds and condense
• What happens when a liquid is cooled further?

  Particles form more bonds and freeze
• What is a limitation of the particle model?

  It doesn't accurately represent particles
• What does the particle model not include?

  Details of forces between particles
• Why are models like particle theory useful?

  They simplify complex concepts
• What are the processes of changing states of matter?

  • Melting: Solid to liquid
  • Boiling/Evaporation: Liquid to gas
  • Condensation: Gas to liquid
  • Freezing: Liquid to solid