1. Gases and their Properties

2. Kinetic-Molecular Theory Gases = large #’s of tiny particles spaced far apart Gases = large #’s of tiny particles spaced far apart Collisions between gas particles and containers are perfectly elastic Collisions between gas particles and containers are perfectly elastic Gases are in continuous, rapid, random motion Gases are in continuous, rapid, random motion The average kinetic energy of a gas depends on the temperature of the gas The average kinetic energy of a gas depends on the temperature of the gas There are no forces of attraction or repulsion between gas particles There are no forces of attraction or repulsion between gas particles

3. Important Characteristics of Gases Pressure = force per unit area Pressure = force per unit area Units =Millimeters of Mercury (mm Hg) Pascals (Pa) Kilopascals (kPa) = 1000 Pa Atmospheres (atm) Conversions : 1 atm. = 760 mm Hg = 101.325 kPa 1 atm. = 760 mm Hg = 101.325 kPa

4. Temperature = average kinetic energy Temperature = average kinetic energy Units =Celsius Kelvin **In order to use gas laws, all temperatures must be in Kelvin** Celsius to Kelvin conversion = C + 273 Kelvin to Celsius conversion = K - 273

5. Volume = amount of space Volume = amount of space Units =Liters Milliliters Standard Temperature & Pressure (STP) -Used to compare volumes of gases STP= 273 K & 1 atm