1. 15-2 Behavior of Gases 15-3 Graphing Gas Behavior

2. Measuring Gases Volume – the amount of space matter fills
Measured in cm3, mL, L
Volume of a gas is the same as the volume of its container
Temperature – measure of the energy of motion of particles
Faster = higher temperature
Pressure – an outward push of a gas on the walls of a container
Pressure = Force/ Area

3. Relating Pressure & Volume
Boyle’s Law
If pressure of a gas is increased = the volume of the gas decreases
If the pressure of a gas is decreased = the volume of the gas increases

4. Relating Pressure & Temperature
If increase temperature of a gas = increase in pressure
If decrease temperature of a gas = decrease in pressure
On long trips truck tires heat up and the pressure increases and the tire can pop

5. Relating Volume & Temperature
Charles’s Law
When temperature of a gas increases = the volume increases
When temperature of a gas decreases = the volume decreases
Basketball left out overnight in cold becomes soft because volume of air inside decreased

6. Graphing Gas Behavior X – axis is horizontal Y –axis is vertical
Graph manipulated variable on x-axis
Y –axis is vertical
Graph responding variable on y-axis
Label each axis with the name of the variable, the units used, and the range of variables

7. Directional Proportional Graphs
If a graph shows a straight line passing through point 0,0 the variables are directional proportional to each other
Ex. Charles’s Law

8. Inversely Proportional Graphs
When a graph forms a curve, the variables vary inversely with each other.
Ex. Boyle’s Law