1. Kinetic Molecular Theory KMT

2. KMT Newtonian Cradle: What happens as two balls are pulled back and then released? Why does this happen?

3. KMT Where the collisions between the balls elastic? Initially Yes, because kinetic energy was transferred with each collision Why did the balls eventually stop swinging? The collisions were not perfectly elastic, some kinetic energy was lost as heat during each collision.

4. KMT - Assumptions Gas consists of large number of particles (atoms or molecules) –Small, hard spheres Particles make elastic collisions with each other and with walls of container There exist no external forces (density constant) Particles, on average, are separated by distances large compared to their diameters -Insignificant volume; relatively far apart from each other

5. KMT - Assumptions No forces between particles except when they collide –No attraction or repulsion between particles Particles in a gas move rapidly in constant random motion –Move in straight paths, changing direction only when colliding with one another or other objects –Average speed of O 2 in air at 20 o C is an amazing 1660 km/h! (1.6km=1mile)