For an ideal gas,which statement is not true?

State whether the following statements are True or False:
$(i)$ Attractive or repulsive forces act between molecules of an ideal gas.
$(ii)$ The potential energy of an ideal gas is zero.
$(iii)$ Molecules of all gases are the same in size.
$(iv)$ Molecules of an ideal gas are perfectly elastic spheres.

According to the kinetic theory of gases,at absolute temperature

Select the incorrect statement about an ideal gas.

The average distance between molecules of an ideal gas at $STP$ is approximately of the order of

According to the kinetic theory of gases,which of the following statements is true?