1. The Gas Laws Boyle’s Law Charles’ Law Gay-Lussac’s Law
Combined Gas Law

2. COPY THIS CHART!!!!

3. Units used to describe gas samples:
Volume
Liter (L)
Milliliter (mL)
1000 mL = 1L
Temperature
Kelvin ONLY
Pressure
Atmosphere (atm)
Kilopascale (kPa)
1 atm = kPa
1 atm = 760 mm Hg
1 atm = 760 torr

4. Boyle’s Law
Boyle’s Law – at constant temperature, the volume of the gas increases as the pressure decreases. The volume of the gas decreases and the pressure increases.
V↑ P↓
Volume L
P1V1 = P2V2
If you squeeze a gas sample, you make its volume smaller.
Pressure (kPa)

5. ↕ Same temperature Moveable piston
Now a container where the volume can change (syringe)
Moveable piston ↕
Same temperature
Volume is 100 mL at 25°C
Volume is 50 mL at 25°C
In which system is the pressure higher? (Which has the greater number of collisions with the walls and each other?)

6. Boyle’s Law—WATCH THIS

7. Charles’ Law
Charles’ Law – at a constant pressure, the volume of a gas increases as the temperature of the gas increases and the volume decreases when the temperature decreases.
V V2
T T2 =
increase AKE
increase the speed of
the particles
the walls of a flexible
container expand –
think of hot air balloons!
Volume L
Temperature (K)

8. A B Steel cylinder (2L) contains 500 molecules of O2 at 400 K
In which system do the O2 molecules have the highest average kinetic energy?
In which system will the particles collide with the container walls with the greatest force?
In which system is the pressure higher? B B B

9. Charles’ Law—WATCH THIS!

10. Gay-Lussac’s Law
Gay-Lussac’s Law – the pressure of a gas is directly proportional to its absolute temperature at a constant volume.
P P2
T T2
Pressure
(atm) =
Temperature (K)

11. To remember how these work. . .
P T V
Think “Public Tele Vision”

12. Gay-Lussac’s Law—WATCH THIS!

13. To remember which constants go with which law . . .
Boyle’s Law – Temperature is constant
Charles’ Law – Pressure is constant
Gay-Lussac’s Law – Volume is constant
BLT
Cheese Pizza
Green Veggies

14. Combined Gas Law P1V1 P2V2 = T1 T2
The equation is found on Table T. Note that all temperatures must be in Kelvin!

15. Combined Gas Law-WATCH THIS!

16. MORE VIDEOS https://safeshare.tv/x/ss5b99376aeafe9#