Kinetic Molecular Theory of Matter

• The kinetic molecular theory of matter provides an overview of the microscopic properties of molecules or atoms and their interactions.
• The kinetic molecular theory describes the microscopic properties of matter and how they translate to the state and other properties of matter.
• The kinetic molecular theory states that:

  (1) Matter is composed of small particles.

  (2) The molecules interact with one another through attractive forces. The strength of these forces is related to the distance between the particles.

  (3) These molecules are always in constant random motion.

  (4) The temperature of a substance is a measure of the average kinetic energy of the

  molecules.
• Atoms are the building blocks of matter.
• Matter can exist as a group of individual atoms or

  as a group of atoms bonded together called molecules.
• The attractive forces between molecules are known as the intermolecular forces.
• Solids have particles with strong intermolecular forces such that their particles are very close to one another.
• Liquids have intermediate intermolecular forces. This makes liquid particles farther from one another compared to those in solids.
• Gases, on the other hand, have particles that are very

  far apart from one another due to weak intermolecular forces.
• All molecules are in constant random motion.
• Solids, due to their strong intermolecular forces, have restricted motion.
• Liquids, having intermediate intermolecular forces, are able to move past each other.
• Gases, having weak intermolecular forces, are able to move in

  relatively long distances before colliding with another molecule.
• Kinetic energy refers to the energy of particles in motion.
• Temperature is a measure of the average kinetic energy of

  molecules. Increasing the temperature will result in a faster motion of the particles.
• A solid is characterized by having a rigid shape and fixed volume.
• Liquids are similar to solids in such a way that their volumes do not change significantly with varying temperatures and pressure.
• Gases have volumes that depend on temperature and pressure.
• Based on the kinetic molecular theory of matter, the state of a matter is determined by two factors — temperature and strength of intermolecular forces.