Behavior of Gases

Behavior of GasesBehavior of Gases

Chapter 3 Section 3Chapter 3 Section 3

Let’s Review:Let’s Review: What is the definition of Volume?What is the definition of Volume?

Amount of space something takes upAmount of space something takes up What is the SI Unit for Volume?What is the SI Unit for Volume?

mm33, but we also use cm, but we also use cm33, mL, L, mL, L What is the definition of Temperature?What is the definition of Temperature?

Average energy of motion of the particles of Average energy of motion of the particles of matter.matter.

Higher Temperature means…??Higher Temperature means…??Faster the particles are movingFaster the particles are moving

What is the definition of Fluid Pressure?What is the definition of Fluid Pressure?Total Force exerted by colliding particles Total Force exerted by colliding particles over an areaover an area

Gas PressureGas Pressure Force of the gas particles divided by Force of the gas particles divided by

the area of the walls of the container.the area of the walls of the container. As Gas Particles increases in a As Gas Particles increases in a

confined container = Pressure confined container = Pressure IncreasesIncreases

What would happen if you opened the container What would happen if you opened the container and provided more volume for the gas particles?and provided more volume for the gas particles?

The pressure would decrease!The pressure would decrease!

Draw a picture of a Draw a picture of a Volleyball.Volleyball.

*Draw & Label the Gas *Draw & Label the Gas Molecules Molecules insideinside + + outsideoutside

of the ball. of the ball. *Label where you think there is *Label where you think there is

Higher PressureHigher Pressure and where and where you think there is you think there is Lower Lower

Pressure.Pressure.

Charles’s LawCharles’s LawWhat happens to gas particles when What happens to gas particles when temperature increases? The particles temperature increases? The particles

move… move… If they move faster, they move farther apart, If they move faster, they move farther apart,

which means…which means…

When the temperature of a gas is When the temperature of a gas is increased at a constant pressure, the increased at a constant pressure, the

volume ______________.volume ______________.When the temperature of a gas is When the temperature of a gas is

decreased, the volume _____________.decreased, the volume _____________.

How do Hot Air Balloons fly?How do Hot Air Balloons fly?

The volume of the hot air increases The volume of the hot air increases when the temperature increases…when the temperature increases…making it less dense than the air making it less dense than the air

outside!outside!

Brain Break!Brain Break!With your partner, Create a riddle or analogy to With your partner, Create a riddle or analogy to

help you remember Charles’s Law. help you remember Charles’s Law.

Boyle’s LawWhen the pressure of a gas at a constant temperature is increased, the volume of the

gas ____________. When the pressure of a gas is decreased, the

volume of the gas _____________.

http://www.chem.iastate.edu/group/Greenbowe/sections/projectfolder/flashfiles/gaslaw/boyles_law_graph.html

Temperature & PressureTemperature & Pressure

As Temperature of a As Temperature of a gas gas INCREASESINCREASES at at a constant volume, a constant volume,

Pressure Pressure INCREASESINCREASES

Why? Why? Particles move faster and Particles move faster and

collide more frequently, collide more frequently, like sand particles on a like sand particles on a

windy beach.windy beach.