Final answer:
The statement that gas molecules attract and repel each other is not a postulate of kinetic molecular theory because the theory assumes no attractive or repulsive forces between gas molecules.
Step-by-step explanation:
The student has asked which of the following is not a postulate of kinetic molecular theory, and the listed options are:
- the size of a gas molecule is negligible
- gas molecules attract and repel each other
- collisions of gas molecules with each other and the walls of the container are elastic
- gas molecules move constantly and randomly though the space they occupy
- the average kinetic energy of a gas molecule is directly proportional to the absolute temperature of the gas
The correct answer to this question is B. gas molecules attract and repel each other. This statement is not a postulate of kinetic molecular theory. In fact, one of the key postulates of the theory is that gas molecules exert no attractive or repulsive forces on each other, which allows their collisions to be elastic, meaning there is no loss of energy during collisions.