Final answer:
As matter is cooled to absolute zero, the particles' kinetic energy decreases and they eventually stop moving. This is explained by the kinetic theory of matter, which states that matter is made up of particles that have varying levels of energy and motion at different temperatures.
Step-by-step explanation:
As a sample of matter is continually cooled, the average kinetic energy of its particles decreases. Eventually, at absolute zero, the particles of matter theoretically stop moving completely. Absolute zero is the lowest possible temperature on the Kelvin scale, and it corresponds to the temperature at which there is no molecular motion.
According to the kinetic theory of matter, all matter is made up of particles that have energy allowing them to move at different speeds. As the temperature decreases, the particles of matter slow down and their kinetic energy decreases. At absolute zero, the kinetic energy of the particles reaches its minimum value.