1. Happy Wednesday! Pick up the handouts Get your assigned chrome- book We are starting Gas Laws today!

2. Kinetic-Molecular Theory and Gas Properties Kinetic-Molecular Theory and Gas Properties

3. Variables Used in Gas Laws Temperature – measure of the kinetic energy of the particles in a substance Volume – the amount of space that a substance occupies Pressure – force of the collisions in a gaseous substance – – What affects pressure?   Container size, temperature, number of particles, particle size Particle Amount and Size

4. Properties of Gases highly compressible and low density – due to the large spaces between gas particles highly compressible and low density – due to the large spaces between gas particles indefinite shape – will take shape of its container indefinite shape – will take shape of its container indefinite volume – will occupy the entire volume of its container indefinite volume – will occupy the entire volume of its container high fluidity – the particles easily glide by one another, allow the gas to flow high fluidity – the particles easily glide by one another, allow the gas to flow

5. Kinetic-Molecular Theory and Gases 1. Gas is composed of particles either molecules or atomseither molecules or atoms 2. Gas particles do not attract or repel one another. Like billiards balls, they bounce off of one anther after a collisionLike billiards balls, they bounce off of one anther after a collision

6. Kinetic-Molecular Theory and Gases 3. Gas particles are in constant, random motion they move in straight line pathsthey move in straight line paths only changing direction when they collide with one another or walls of containeronly changing direction when they collide with one another or walls of container 4. All gas particle collisions are elastic collisions energy transferred from one particle to another without a loss of kinetic energy.energy transferred from one particle to another without a loss of kinetic energy.

7. 5. The amount of kinetic energy, how fast the particles move, depends on temperature. –Higher temperature, move faster –Lower temperature, move slower –At absolute zero (0 K – lowest possible temperature) – NO movement

8. Definitions Effusion – gradual movement of a gas through a small opening Effusion – gradual movement of a gas through a small opening Diffusion – gradual mixing of gases due to constant random motion Diffusion – gradual mixing of gases due to constant random motion