1. Equilibrium: How is your balance? Physical Science December 12, 2011 Ms Cilli pages 216-219

2. Physical Science pages 216-219

3. Objectives Identify and describe physical and chemical equilibria. Identify and describe physical and chemical equilibria. Describe the factors affecting chemical equilibrium. Describe the factors affecting chemical equilibrium.

4. Physical Science pages 216-219 Ever rode a seesaw?

5. Physical Science pages 216-219 Equilibrium A state in which the forward and reverse paths of a change take place at the same rate A state in which the forward and reverse paths of a change take place at the same rate What are the two types of changes? What are the two types of changes? 1. 1. 2. 2.

6. Physical Science pages 216-219

7. When physical change does not go to completion, a physical equilibrium is established When physical change does not go to completion, a physical equilibrium is established The forward and reverse changes are the same The forward and reverse changes are the same Example: slushie Example: slushie Physical Science pages 216-219

9. Occurs when the reaction does not go to completion Occurs when the reaction does not go to completion Example: Example:

10. All together now… A physical equilibrium is established between the forward and reverse reactions when the physical change does not go to completion A chemical equilibrium is established between the forward and reverse reactions when the chemical change does not go to completion Physical Science pages 216-219

11. When a change is introduced into a system in equilibrium, the equilibrium shifts in the direction that relieves the change When a change is introduced into a system in equilibrium, the equilibrium shifts in the direction that relieves the change

12. 1. 1. 2. 2. 3. 3. Physical Science pages 216-219

13. If energy is added to one side, the other side will release it If energy is added to one side, the other side will release it Physical Science pages 216-219

14. If the reaction is endothermic (adding heat), when the reaction is reversed the heat will be ________. (exothermic). If the reaction is endothermic (adding heat), when the reaction is reversed the heat will be ________. (exothermic). Physical Science pages 216-219

15. What happens when you squeeze a balloon? What happens when you squeeze a balloon? Physical Science pages 216-219

16. If you increase the pressure on one side, it will shift direction to ________ the pressure If you increase the pressure on one side, it will shift direction to ________ the pressure Physical Science pages 216-219

17. What happens if you increase the amount of ingredients (reactants) when making a cake? What happens if you increase the amount of ingredients (reactants) when making a cake? Physical Science pages 216-219

19. ClosureClosure True or false: True or false: In chemical equilibrium, the rate of forward reaction does not equal the rate of the reverse reaction. The three factors that affect chemical equilibrium are: The three factors that affect chemical equilibrium are: A. Pressure B. Temperature C. Concentration D. Volume E. Only A, B, and C

20. Assignment: Independent Work: Read section 7.5 in the book Start studying for the test Finish the study guide Homework: Section 7.5 HW due Tuesday, December 13 th by 8PM Independent Work: Read section 7.5 in the book Start studying for the test Finish the study guide Homework: Section 7.5 HW due Tuesday, December 13 th by 8PM Physical Science pages 216-219