Kinetic Theory of Matter

• Here are the main points of the kinetic theory
  of matter:
• All matter is made of atoms and molecules that act like tiny particles.
• These tiny particles are always in motion. The higher the temperature of the substance, the faster the particles move.
• At the same temperature, more-massive (heavier) particles more slower than less-massive (lighter) particles.
• The states of matter differ physically from
  one another.
• Particles of a solid, such as iron, are in fixed positions.
• In a liquid, such as cooking oil, the particles are closely packed, but they can slide past each other.
• Gas particles are in a constant state of motion
  and rarely stick together.
• Solids have a definite shape and volume.
• The structure of a solid is rigid, and the particles have almost no freedom to change position.
• Crystalline solids have an orderly arrangement of atoms or molecules.
• Amorphous solids are composed of atoms or molecules that are in no particular order.
• Liquids change shape, but not volume.
• The particles in a liquid move more rapidly than those of a solid—fast enough to overcome the forces of attraction between them.
• The particles in a liquid can slide past each other, flowing freely. Liquids can take the shape of the container they are put into.
• Liquids have surface tension, the force acting at the surface of a liquid that causes a liquid, such as water, to form spherical drops.
• Gases are free to spread in all directions.
• The particles of a gas move fast enough to break away from each other.
• The space between gas particles can change, so a gas expands to fill the available space.
• A gas can also be compressed to a
  smaller volume.
• Plasma is the most common state of matter.
• Plasma is a state of matter that starts as a gas and then becomes ionized.
• Plasmas conduct electric current, while gases
  do not.
• Natural plasmas are found in lightning and fire. The glow of a fluorescent light is caused by an artificial plasma, created by passing electric currents through gases.