1. IV. Gas Laws Continued

2. A. Dalton’s Law
Total pressure of a mixture of gases is equal to the sum of the pressures of all gases in the mixture
Ptotal = P1 + P2 + P3 + … + Pn
Make sure that all pressure units are the same!!

3. Example: If 5 atm of CO2, 10 atm of H2O(g), and 5 atm of NO2 are mixed in a container, what is the total pressure of the container?
Ptotal =Pco2 + PH2O + PNO2
Ptotal = 5 atm + 10 atm + 5 atm = 20 atm

4. Practice #1
A container contains 3 gases: CO2, H2O, and O2. The total pressure is measured to be 234 kPa. The partial pressure of CO2 is 50 kPa and the partial pressure of O2 is 100 kPa. What is the partial pressure of H2O?

5. B. Charles’ Law
The volume of a gas is directly proportional to the temperature in KELVIN.
Pressure is constant
**Temperature must be in KELVIN
**Volumes must be in the same unit

8. Practice #2
A man heats a balloon in the oven. If the balloon initially has a volume of 0.4 L and a temperature of 20oC, what will the volume of the balloon be after he heats it to a temperature of 250oC?

9. C. Gay-Lussac’s Law
Temperature and pressure of a gas are directly proportional
Volume is constant
**Temperature must be in KELVIN
**Pressures must be in the same unit

12.
Practice #3
If a gas is cooled from 323 K to 273 K and the volume of the gas is kept constant, what would the final pressure be if the original pressure was 750 mmHg?

13. D. Boyle’s Law
The pressure of a gas is inversely proportional to its volume
Temperature is held constant
**Pressure must be in the same unit
**Volume must be in the same unit

16. Practice #4
15 L of air is initially at sea level (1 atm) and is then taken to Denver where the new pressure is 86.1 kPa. What is the new volume of the balloon? 1 atm = 760 torr = kPa = 14.7 psi

17. **Volume must be in the same unit
E. Avogadro’s Law
The volume of a gas is directly proportional to the number of moles of gas
Temperature and pressure are constant
**Volume must be in the same unit