1. The Ideal Gas Law

2. The Perfect Gas Ideal gas – an imaginary gas whose particles are infinitely small and do not interact with each other No gas obeys the gas law under all conditions The ideal gas has no forces of attraction or repulsion and is made of particles that do not occupy a volume

3. Ideal Gas Law PV = nRT P = Pressure V = volume N = number of moles T = temperature R = gas constant = 8.314 L ● kPa mol ● K Or 0.0821 L ● atm mol ● K

4. Ideal Gas Law Very good at predicting gas behavior at STP But at lower volumes and higher pressures, real gases have a mind of their own

5. Dalton’s Law of Partial Pressures Partial Pressure – the pressure of each gas in a mixture The total pressure of a gas is a sum of the pressure of its parts P total = P A + P B + P C +…..

6. How many moles of gas are contained in 22.41 L at 101.325 kPa and 0 ° C?

7. How many moles of air molecules are contained in a 2.00 L flask at 98.8 kPa and 25.0 ° C?

8. Sample Dalton’s Law Problem A tank contains nitrogen and oxygen. If 75% of the tank contains nitrogen and the total pressure of the tank is 67. 32 atm. What is the partial pressure of oxygen in atm?