Final answer:
A real gas does not behave according to the kinetic-molecular theory which assumes no volume and no intermolecular forces for the gas molecules. Real gases deviate from ideal behavior at high pressures and low temperatures due to actual molecular volume and interactive forces between molecules. Most gases, however, come close enough to these ideal assumptions to make the kinetic theory a useful tool in many situations.
Step-by-step explanation:
A gas that does not behave according to the assumptions of the kinetic-molecular theory is known as a real gas. The kinetic molecular theory of gases states that ideal gases have no volume or intermolecular forces, a condition that is only approximated by real gases under certain conditions. When the pressure of a gas is relatively high, real gases often deviate from the ideal gas law, which is the most evident difference between real gases and ideal gases.
The properties of real gases differ from ideal gases in two crucial ways: real gases have nonzero molecular volumes and their molecules interact with attractions or repulsions depending on their molecular structures. These interactions and the finite volumes of gas particles cause deviations under high pressure or low temperature conditions from the behavior described in the kinetic-molecular theory, which applies best to ideal gases.
Despite these differences, many gases still adhere closely enough to the principles of the kinetic theory that it is generally well accepted as a good approximation for understanding gas behavior. However, factors such as the liquefaction of gases are properties of real gases that are not predicted by the theory. Understanding these deviations is essential for accurate prediction and manipulation of gas behavior in scientific and industrial applications.