Part I: Units of Measurement for Gas Laws
For the following questions, use the following answer choices to indicate what each unit of measurement is used to measure (pressure, volume, or temperature).
1. atm
2. kPa
3. L
4. oC
5. torr
6. K
7. mL
8. cubic centimeters (cm3)
Convert the following:
1. 453 K to oC
2. 80 oC to Kelvin.
Part III: Relationships between Pressure, Volume, and Temperature of a Gas
1. What kind of relationship exists between the pressure and volume of a gas at a constant temperature?
2. What kind of relationship exists between the temperature and volume of a gas at a constant pressure?
3. If you were to graph the relationship between pressure and temperature, which graph (1 or 2) would it be the most similar to? Why?
4. A sample of nitrogen gas starts at 20 L and increases to 40 L. Would you expect that the pressure will increase or decrease? Why?
5. A student fills a flask with 5.0 moles of nitrogen gas and then seals the flask. The student warms the flask using a Bunsen burner. What can you predict will happen to the pressure of the gas? Why?
6. Mountain climbers can often freeze to death on the top of mountains because the air on the top of the mountains has a low volume. Explain using a gas law why this would make the temperature low.
Part IV: Gas Law Calculations
1. A balloon is heated under constant pressure so that it will expand. Initially, the volume is 56L at 45oC. If the balloon is heated so that it expands to 130L, what is the new temperature (in Celsius) of the gas in the balloon?
2. At 85°C, a flask contains 1789 cm3 of a gas at a pressure of 99.6 kPa. If volume is kept constant, what is the new pressure of the gas if the gas is heated to 108°C?
3. A weather balloon at Earth’s surface has a volume of 4 L at 31oC and 1.0 atm. If the balloon is released and the volume reaches 4.8 L at 0.9 atm, what is the temperature in Celsius?
4. What is the volume of a sample of gas that contains 1.2 mol at 12 o C and 1.3 atm?
5. A sample of air has a volume of 140.0 mL at 67 0C. At what temperature would its volume be 50.0 mL at constant pressure?
6. The pressure exerted on a 240.0 mL sample of hydrogen gas at constant temperature is increased from 0.428 atm to 0.724 atm. What will the final volume of the sample be?
7. 0.2 L of gas is in an engine cylinder with an initial pressure of 2558 mm Hg at a constant temperature. The gas is expanded inside the cylinder as the piston pushes up to have a volume of 0.3 L. What is the final pressure of the gas after the expansion?
Part I: Units of Measurement for Gas Laws
1. atm - Pressure
2. kPa - Pressure
3. L - Volume
4. oC - Temperature
5. torr - Pressure
6. K - Temperature
7. mL - Volume
8. cubic centimeters (cm3) - Volume
Convert the following:
1. To convert from Kelvin (K) to Celsius (oC), subtract 273.15. Therefore, 453 K = 453 - 273.15 = 179.85 oC.
2. To convert from Celsius (oC) to Kelvin (K), add 273.15. Therefore, 80 oC = 80 + 273.15 = 353.15 K.