1. Gas Laws Notes

2. How do we measure gases? We have to consider 3 things:
Volume, temperature, and pressure

3. Measuring Gases You already know what volume & temperature are!
Volume (mL, L, cm3, etc.)
Temperature (°C or K)
Volume = amount of space that matter fills
Temperature = measure of average kinetic energy of the particles in a substance

4. Pressure
Gas particles are constantly colliding with one another and as a result push on the walls of whatever container they are in.
Pressure = force of the outward push divided by the area of the walls of the container

5. Pressure and Volume
Boyle’s Law If gas at constant temperature has an  in pressure, the volume ; When the pressure is , the volume 
Formula: P1V1 = P2V2

7. Practice Problems – Boyle’s Law
What kind of relationship do pressure and volume exhibit (at constant temperature)? Directly proportional or inversely proportional?
A balloon has a volume of 1 L at a pressure of 500 kPa. What is the new pressure if the balloon is changed so that the volume is 0.3 L?
A balloon of helium occupies L at 9.0 kPa. What is the new volume if the pressure drops to 4.0 kPa?

8. Volume and Temperature
Charles’ Law: Under constant pressure, if temperature is , volume  and if temperature is , volume .
T1 / V1 = T2 / V2
Where T = temperature in Kelvin (°C = K) and V = volume

9. Charles’ Law

10. Practice Problems – Charles’s Law
What kind of relationship do volume and temperature exhibit (at constant pressure)? Directly proportional or inversely proportional?
What would be the resulting volume of a 4.8 L balloon at 10.0°C that was placed in a container of dry ice at - 78°C?
A L hot air balloon at 299°C had its volume changed to Liters. What is the new temperature of the balloon in °C?

11. Pressure and Temperature
Gay Lussac’s Law: If volume is constant (gas is in a closed, rigid container), and temperature is , the pressure . When temperature is , pressure 
P1 / T1 = P2 / T2 where T is in Kelvin

13. Practice Problems: Gay-Lusaac’s Law
What kind of relationship do pressure and temperature exhibit (at constant volume)? Directly proportional or inversely proportional?
If a gas is cooled from K to K and the volume is kept constant what final pressure would result if the original pressure was mm Hg?
The temperature of a sample of gas in a steel container at kPa is increased from °C to 1.00 x 103 °C. What is the final pressure inside the tank?