Answer: D. They are made up of hard spheres that are in random motion.
Explanation:
A gas is a state of aggregation of matter in which, under certain conditions of temperature and pressure, its molecules interact weakly with each other, without forming molecular bonds, adopting the shape and volume of the container that contains them and tending to separate everything possible because of its high concentration of kinetic energy.
The molecules of a gas are practically free and have the ability to be distributed throughout the space in which they are contained because the gravitational forces and attraction between them are practically negligible compared to the speed at which they move. .
Therefore, gas molecules do not travel specific trajectories or vibrate in a stationary position, instead they move quickly and randomly through the entire space of the container that contains them.
