Chapter 3 Lesson 2 “The Gas Laws” Gas Review 1. Indefinite shape 2. Indefinite volume 3. Takes shape of container 4. Fast moving particles (1600 km/hr)

I. Pressure A.Def – the amount of force exerted over an area. 1. Tires – gases push on the outside walls of tires B. Formula - P = F / A C. Measured in Pascals (N/m 2 ) kPa at Sea level

II. Boyle’s Law (Pressure and Volume Law) A.Def – When the volume of a gas is decreased the pressure goes up. When the volume of a gas is increased the pressure goes down. 1. Temp. must remain constant 2. P 1 x V 1 = P 2 x V 2

III. Charles’ Law (Temperature Law) A.Def – The volume of a gas increases with temperature (energy). The volume of a gas decreases with a loss of temperature (energy). 1. Energy (heat) causes gases to move faster  more pressure on container. 2. Loss of heat causes gases to move slower  less pressure on container. 3. V 1 V 2 T 1 T 2 4. Temp. must be in Kelvins!! =

IV. Combined Gas Law A.Combines all aspects B.Formula P 1 x V 1 P 2 x V 2 T 1 T 2 =

Practice Problems 1.A gas has a volume of 5.0 L at a pressure of 50 kPa. What happens to the volume when the pressure is increased to 125 kPa? The temp does not change. 2.Gas stored in a tank at 273 K has a volume of 10.0 L. If the temperature goes up to 305 K, what would the new volume of the tank need to be? 3.At 275 K, the gas in a cylinder has a volume of 0.25 L. The gas is allowed to expand to 0.29 liters. What must the final temperature of the gas be assuming pressure stays the same? 4.A gas at 310 K has a pressure of 100 kPa and a volume of 20.0 L. If the temperature increases to 350 K and the volume remains constant, what is the new pressure of the gas? (Use Combined Gas Law)