How is the kinetic theory of matter related to gases?

The kinetic molecular theory tells us how gas molecules are supposed to behave. In doing this, it makes a few assumptions about how gases behave. Let's have a look at them and see if they're right:

• Gas particles are infinitely small. In the real world, atoms and molecules are not infinitely small, making this incorrect.

• Intermolecular forces can be ignored. Because all gas particles experience intermolecular forces of one kind or another, this is also incorrect.

• Gas particles undergo completely elastic collisions (i.e. collisions that don't result in the loss of energy). Perfectly elastic collisions don't happen because some energy isn't transferred, making this wrong.

• The kinetic energy of gas particles is directly proportional to the temperature in Kelvin. As far as I know, this is correct.

OK.