states of matter

• what theory attempts to explain the three states of matter?

  particle ( kinetic) theory
• what are the three main assumptions of the particle theory?

  1. small
  2. inelastic
  3. spheres
• In solids, strong attractive forces hold the particles in place, so that they can only vibrate in position. 

  As the substance is heated, the particles gain energy and vibrate faster and faster. Eventually, the particles have so much energy that they can overcome the forces holding them together, and the substance melts into a liquid.
• hen a solid is heated, energy is transferred to the particles' kinetic energy stores, causing them to vibrate faster. 
• When a gas is heated, the particles gain kinetic energy and move faster. 

  If the gas is trapped within a container that cannot expand, it means that the volume of the gas is fixed, and so the pressure inside the container increases. 
• when a gas is heated in a fixed container the pressure will increase
• when a gas is in a expandable container, the volume will increase