Mathematical Relationships between P, V, and T

Marshmallow & Bell Jar demo!

Pressure and Volume: Boyle’s Law Pressure and volume are inversely (indirectly) proportional to each other If pressure goes up, what happens to volume? P1V1 = P2 V2

What variables must remain the same in order for this equation to work? Temperature amount of gas particles

What kind of relationship is there between temperature and volume What kind of relationship is there between temperature and volume? (Direct or inverse?)

Skinny Egg!

Charles’ Law: If pressure and the number of particles of gas stay the same, the volume is directly proportional to the Kelvin temperature.

What was the relationship between Pressure and temperature What was the relationship between Pressure and temperature? (Direct or inverse?)

Gay-Lussac’s Law P1 P2 T1 T2 = If volume and the number of gas particles remain the same, the pressure is proportional to the Kelvin temperature. P1 P2 T1 T2   =

Combined Gas Law Increase Decrease When more than two gas variables change at once Example: balloon rising into the sky What would happen to the balloon volume according to Boyle’s law? What would happen to the balloon volume according to Charles’ law? Conflicting outcomes: Will the balloon expand or shrink? Increase Decrease

Combined Gas Law If you know the relationship among temperature (T), pressure (P), and volume (V) of a gas, you can determine the volume of the gas for other pressures and temperatures.