1. REACTION RATES & FACTORS AFFECTING EQUILIBRIUM
CHAPTER 3 ACTIVITY 5
REACTION RATES &
FACTORS AFFECTING EQUILIBRIUM

2. Energy Diagrams
2H2 + O2
2H2O
E of products
A.E. E
E of reactants
Activated
Complex
Energy
Reaction Progress
A.E. (activation energy): minimum energy needed for a reaction to occur
Activated Complex: transitional structure formed from an effective collision.

3. Not Every Collision Produces Products
Reactants must:
1. Collide with the correct orientation
2. Have enough energy to produce
products.

4. The Reaction Process
Collision Theory: Explanation of reactions as a result of collisions.
Particles must collide
Particles must collide in the correct orientation
Collision must be energetic enough to disrupt bonds

5. Catalyst
A substance that increases the rate of reaction without being used up itself in the reaction.
Energy barrier w/o catalyst
Energy barrier w catalyst
Reactants
Energy
Products
Reaction Progress

7. Exothermic vs. Endothermic
A process that loses heat to its surroundings.
Fe2O3(s) + CO(g) Fe(s) + CO2(g) kJ
Endothermic:
A process that absorbs heat from its surroundings.
2NaHCO3(s) kJ Na2CO3(s) + H2O(g) + CO2(g)

9. Is the following an example of an exothermic or endothermic reaction?
Reactants
Potential
Energy
EXOTHERMIC=energy is released
Products
Reaction Progress

10. Is the following an example of an exothermic or endothermic reaction?
Products
Potential Energy
Reactants
ENDOTHERMIC=energy is absorbed
Reaction Progress

11. Factors Affecting Reaction Rates
1. Temperature
2. Concentration
3. Particle Size
4. Catalysts

12. Factors Affecting Reaction Rates
1. Temperature WHY
Temp Rate Kinetic Energy

13. Factors Affecting Reaction Rates
2. Concentration WHY
Conc Rate More Particles
increases collision
frequency

14. Factors Affecting Reaction Rates
3. Particle Size WHY
Particle Rate Smaller Particle
Size size increases
the surface area

15. Factors Affecting Reaction Rates
4. Catalyst WHY
Adding a Rate Activation Energy
Catalyst

16. FACTORS AFFECTING EQ. Le Chatelier’s Principle
Reactions will stabilize and establish equilibrium. If this system is disturbed from equilibrium, it will shift in order to reduce the disturbance.
When any of the following three things are changed, the system will change to re-establish equilibrium.
Concentration
Temperature
Pressure
Equilibrium
R P
Systems Equilibrium

17. Know the Difference Factors Affecting: Solubility Reaction Rates
Equilibrium
Temperature
2. Agitation
2. Concentration
3. Particle Size
3. Pressure
4. Catalyst

18. Concentration H2CO3 CO2 + H2O If we add CO2, more H2CO3 will be made
If we remove CO2, more CO2 & H2O will be made

19. Concentration H2CO3 CO2 + H2O
If we remove H2CO3, more H2CO3 will be made
If we add H2CO3, more CO2 & H2O will be made

20. Temperature 2SO2 + O2 2SO3 + heat
If we add heat, more reactants will be made in order to absorb the excess heat
If we remove heat, more products will be made in order to replace the heat that has been removed.

21. Pressure Only Gases Are Affected! N2 + 3H2 2NH3
If we increase pressure, more products will be made (less moles)
4 moles
If we decrease pressure, more reactants will be made (more moles)
2 moles

22. Review
Reactions will stabilize and establish equilibrium. When any of the following three things are changed, the reaction will change to re-establish equilibrium.
Concentration
Temperature
Pressure
R = P