CHAPTER 5

Explosions

Caused when a chemical reaction releases a large amount of gas and energy very quickly

Explosion sends a pressure wave through surrounding materials

Usually oxidation or decomposition rxnOxidation – combo of 2 substances making

oneDecomp – one compound is broken down

into 2+

Properties of gases

Kinetic molecular theory – gas behaviorMany particles moving rapidly & randomlyParticles in gas are smaller than the space b/t

them –most of Vol = empty spaceWhen particles collide, no net loss of energyAs temp increases, so does average kinetic

energy of its particlesNo force of attraction b/t particles and other

things

Relationship b/t Temp, Pressure, & Volume

Gas expands to fill space/containerVol , pressure

If And Then

Temp increases Vol is constant Pressure increases

Temp increases Pressure is constant

Vol increases

Vol increases Temp is constant Pressure decreases

Vol increases Pressure is constant

Temp increases

Pressure increases

Temp is constant Vol decreases

Pressure increases

Vol is constant Temp increases

Combined Gas Law

P = Pressure (kPa) (= kiloPascals)V = Volume (L) (= liters)T = Temperature (K) (= Kelvin)Predict how Temp, Vol, or Press will

change when conditions change

Under certain conditions, pressure increases until container can no longer hold gas

Container explodes

Problem

The volume of a gas-filled balloon is 30.0 L at 313 K and 153 kPa pressure. What would the volume be at standard temperature and pressure (STP)?

Knowns : V1 = 30.0 LT1 = 313 KP1 = 153 kPaT2 = 273 K (standard temp)P2 = 101.3 kPa (standard pressure)