Science 10: LAS Quarter 4: WEEK 1-2
The kinetic molecular theory of matter explains how matter can change among the
phases of solid, liquid, and gas. All particles have energy, and the energy varies depending
on the temperature the sample of matter is in, which determines if the substance is a solid,
liquid, or gas. Solid particles have the least amount of energy, and gas particles have the
greatest amount of energy.
The temperature of a substance is a measure of the average kinetic energy of the
particles. A change in phase may occur when the energy of the particles is changed.
The kinetic molecular theory of matter offers a description of the microscopic
properties of atoms (or molecules) and their interactions, leading to observable macroscopic
properties (such as pressure, volume, temperature). An application of the theory is that it
helps to explain why matter exists in different phases (solid, liquid, and gas) and how matter can change from one phase to the next.