Kinetic Model of Matter 101

Main Idea(s)

  • Matter is made of tiny particles (atoms or molecules) that are in random and continuous motion.

Effects of Temperature on Molecular Motion

  • When temperature increases, the average kinetic energy of the molecules increases. This leads to increase in the average speed of the molecules, resulting in
    • the particles collide with the wall/other particles (if they are present) more vigorously and frequently.
    • the particles move faster and change direction of their motion more frequently.
  • In the case of temperature decreases, everything goes in reversal mode.

Shape and volume

  • For gas, it has no fixed shape and no fixed volume. Two factors are responsible for that. Molecules in gas have very weak inter-molecular bonds between them and they move about randomly at very high speed.