Ideal Gases vs. Real Gases

An ideal gas is a theoretical gas which perfectly fits into the equation PV= nRT.
An ideal gas is different from a real gas in many ways. An ideal gases\' mass
can be disregarded in the equation because it has none; this is because an ideal
gas is said to be a particle and particles do not have any mass. Ideal gases
obtain no volume unlike real gases which obtain small volumes. Also, since
ideal gas particles excerpt no attractive forces, their collisions are elastic.

Real gases excerpt small attractive forces. The pressure of an ideal gas is
much greater than that of a real gas since its particles lack the attractive
forces which hold the particles back when they collide. Therefore, they collide
with less force. The differences between ideal gases and real gases can be
viewed most clearly when the pressure is high, the temperature is low, the gas
particles are large, and when the gas particles excerpt strong attractive forces.

Monoatomic gas molecules are much closer to ideal gases than other particles
since their particles are so small. Because of the differences between ideal
and real gases, Van der Waals created an equation to relate the two.

Category: Science