States of Matter with the Kinetic Molecular Theory

Kinetic molecular theory first made a name for itself when scientists attempted to explain and predict the properties of gases and, in particular, how those properties changed with varying temperature and pressure. The idea emerged that the particles of matter within a gas (atoms or molecules) undergo a serious amount of motion as a result of the kinetic energy within them. 

Kinetic energy is the energy of motion. Gas particles have a lot of kinetic energy and constantly zip about, colliding with one another or with other objects. The picture is complicated, but scientists simplified things by making several assumptions about the behavior of gas pcirticles. These assumptions are called the postulates of the kinetic molecular theory. They apply to a theoretical ideal gas  

Gases consist of tiny particles (atoms or molecules) that are always in constant random motion. 

Particle collisions are elastic (perfectly bouncy, with no loss of energy). 

The gas particles are assumed to neither attract nor repel one another. 

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