states of matter

• What holds the particles in a solid together?

  Strong forces of attraction
• Why do solids have a definite shape and volume?

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

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

  They gain energy and vibrate more
• What occurs at the melting point?

  Particles break free of their bonds
• What type of forces exist between particles in liquids?

  Weak forces of attraction
• Why do liquids have a definite volume?

  Particles tend to stick together
• How do liquids behave in a container?

  They flow to fit the container
• What happens to liquid particles when heated?

  They gain energy and move faster
• What is the boiling point?

  The temperature where liquids boil
• 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?

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

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

  Pressure increases
• What occurs when gas is cooled down?

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

  It freezes into a solid
• What does the particle model not include?

  Details of forces between particles