The ideal gas law can be derived from the kinetic theory of gases and relies on the assumptions that (1) the gas consists of a large number of molecules, which are in random motion and obey Newton’s laws of motion; (2) the volume of the molecules is negligibly small compared to the volume occupied by the gas; and (3) …

The ideal gas law assumes that gases behave ideally, meaning they adhere to the following characteristics: (1) the collisions occurring between molecules are elastic and their motion is frictionless, meaning that the molecules do not lose energy; (2) the total volume of the individual molecules is magnitudes smaller …

For a gas to be “ideal” there are four governing assumptions: The gas particles have negligible volume. The gas particles are equally sized and do not have intermolecular forces (attraction or repulsion) with other gas particles. The gas particles move randomly in agreement with Newton’s Laws of Motion.

Generally, a gas behaves more like an ideal gas at higher temperature and lower pressure, as the potential energy due to intermolecular forces becomes less significant compared with the particles’ kinetic energy, and the size of the molecules becomes less significant compared to the empty space between them.

At high pressures (small volumes), finite particle volumes lower the actual volume available to the gas particles, resulting in a pressure higher than the ideal gas value.

What would be the greatest effect on the ideal gas law if there is a slight attractive force between the molecules? At low temperatures, the pressure would be greater than that predicted by the ideal gas law. At high temperatures, the pressure would be greater than that predicted by the ideal gas law.

Clausius model. The Clausius equation (named after Rudolf Clausius) is a very simple three-parameter equation used to model gases.

At low pressure, there are generally less collisions between the molecules. Since the intermolecular forces depend on the distance between the molecules (the closer the molecules, the stronger the forces), less collisions means also a larger average distance between the molecules, therefore fewer intermolecular forces.

helium

However it would be necessary to get close to absolute zero before Hydrogen would condense into a liquid. Hydrogen gas H2 is very stable and does not form any significant inter molecular forces, or attractions. This makes Hydrogen close to being an ideal gas.

A real gas is a gas that does not behave according to the assumptions of the kinetic-molecular theory. In summary, a real gas deviates most from an ideal gas at low temperatures and high pressures. Gases are most ideal at high temperature and low pressure.

The term ideal gas refers to a hypothetical gas composed of molecules which follow a few rules: Ideal gas molecules do not attract or repel each other. The only interaction between ideal gas molecules would be an elastic collision upon impact with each other or an elastic collision with the walls of the container.