Physical Characteristics of Gases The Kinetic Molecular Theory of Matter
Objectives List the physical properties of gases Use the KMT to explain the physical properties of gases.
Kinetic Molecular Theory of Gases KMT- The particles of matter are in constant motion. Ideal Gas – a gas that behaves according to the kinetic molecular theory.
Kinetic Molecular Theory of Gases 1.Gases are made up of tiny particles. - Usually atoms or molecules
Kinetic Molecular Theory of Gases 2.The particles of a gas are far apart from each other. The volume of gas particles is insignificant relative to the space between the particles
Kinetic Molecular Theory of Gases 3.The particles of a gas are in constant motion and collide with each other and the walls of their container. The collisions are elastic; no K.E. is lost. Collisions exert a force -pressure Specian's Phun machines: Ideal gas – YouTubeSpecian's Phun machines: Ideal gas – YouTube
Kinetic Molecular Theory of Gases 4.The particles of a gas do not exert any force on each other.
Kinetic Molecular Theory of Gases 5.Temperature is a measure of the average kinetic energy of the particles of a gas. Kinetic Energy in a Gas - YouTube
Properties of Gases Expansion of gases No definite shape or volume Expand to fill their container
Properties of Gases Fluidity of Gases Gases have the ability to flow.
Properties of Gases Low Density 1 mole of H 2 20 o C: 18 mL 1 mole of H o C and 1 atm: 22.4 L
Properties of Gases Compressibility Gases can be easily compressed
Properties of Gases Diffusion and Effusion Diffusion –mixing of particles due to random motion of particles Effusion – process in which gases past through a tiny opening
Deviations from Ideal Gas Behavior At low temperatures and high pressures, gases do not follow ideal gas behavior. 1.The volume of the particles is significant. 2.Intermolecular forces become important. Real gas – one that does not behave according to the KMT