Chemistry - Ideal gas-kinetic theory of gases

Can an ideal gas be liquefied? Explain
An ideal gas has no force of attraction between its molecules. It therefore can not form a liquid or a solid as these states of matter require some force of attraction to be present between the molecules.
Why does a real gas behave as an ideal gas at high temperatures and low pressures?
At high temperatures speed of the molecules is high enough to overcome any force of attraction that is present. Low pressures indicate molecules are travelling in a large volume of space which makes their molecular volume insignificant when compared to the volume of space they travel in.
Compare and state the differences between a real gas and an ideal gas.
A real gas can be liquefied and therefore has intermolecular forces acting between its molecules. An ideal gas does not.
A real gas has particles with a definite volume. An ideal gas has particles with negligible volume compared to the volume of space the molecules travel in.
Real gas molecules collide with each other and the walls of the container losing energy in the process. Ideal gas molecules undergo elastic collisions.
Explain why gases are easily compressed.
A large volume of space exists between gas molecules. We can say that a gas is mainly empty space. We can therefore reduce the volume of gases with ease.
What is meant by the average kinetic energy of gas molecules at a given temperature?
Not all molecules of a gas have the same speed at a particular temperature. As the temperature rises the average speed of the molecules increases. Click for a more detailed explanation.
Jonathon pumps his bicycle tyres using a hand pump. The nozzle gets very hot as gas is compressed. What part of the kinetic theory is not obeyed by the compressed air?
Collisions between molecules and with the walls of the nozzle should be elastic (no energy given out). The production of heat due to a rapid rate of collisions indicates that collisions are not elastic.

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Kinetic theory of gases
		Basic points of the kinetic theory of gases 1) The volume of gas molecules is negligible compared to the volume of space in which they move. 2) Gas molecules move in a straight line between frequent collisions with the walls of the container and themselves. 3) All collisions are elastic, i.e. no energy is lost. 4) There are negligible forces acting between molecules. 5) The average kinetic energy of the gas molecules is directly proportional to the temperature. Many of the properties of gases can be explained in terms of the kinetic theory. The kinetic theory describes the behaviour of an *ideal gas.*
Now we know that we can liquefy gases at sufficiently low temperatures. This indicates that attractive forces do exist between molecules. The requirement of the kinetic theory that attractive forces between molecules be negligible, is not satisfied at high pressures and low temperatures. At high pressures and low temperatures attractive forces take over and the volume of gas molecules is significant when compared to the volume of space in which they move. However, at high temperatures and low pressures real gases do behave as ideal gases meeting every requirement of the kinetic theory.
Can an ideal gas be liquefied? Explain Why does a real gas behave as an ideal gas at high temperatures and low pressures? Compare and state the differences between a real gas and an ideal gas. Explain why gases are easily compressed. What is meant by the *average kinetic energy* of gas molecules at a given temperature? Jonathon pumps his bicycle tyres using a hand pump. The nozzle gets very hot as gas is compressed into it. What part of the kinetic theory is not obeyed by the compressed air? Solutions