1. Gases: Mixtures and Movements Chapter 14.4

2. Standards 4b. Students know the random motion of molecules explains the diffusion of gases. 4i. Students know how to apply Dalton’s Law of partial pressures to describe the composition of gases.

3. Dalton’s Law Partial Pressure: the contribution of each gas in a mixture that helps to make the total pressure In a mixture of gases, the total pressure is the the sum of the partial pressures of the gases. P total = P1 + P2 + P3 + …

4. Dalton’s Law Dalton’s Law of Partial Pressures: at a constant volume and temperature, the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of the component gases

5. Sample Problem #26

6. Practice Problem #27

7. Sample Problem #28

8. Sample Problem #29

9. Diffusion Diffusion: the tendency of molecules to move toward areas of lower concentration until the concentration is uniform throughout. Effusion: gas escapes through a tiny hole in a countainer, Gases of lower molar mass diffuse and effuse faster than gases of higher molar mass.

10. To Do In Class: Dalton’s Law of Partial Pressures Worksheet HW: Pg 32: #33-38 & Elements Handbook