1. Mr. Quinn & Ms. Tom March 17, Aim: Why do the factors we have studied affect rate of reaction? Do Now:
What effect do the factors we have learned about have on rate of reaction?
As temperature increases, rate of reaction
As surface area increases, rate of reaction
As pressure increases, rate of reaction
As concentration increases, rate of reaction
Adding a catalyst rate of reaction.

2. Introduction: How does each factor work?
Temperature increases rate of reaction because
The number of collisions increases
Each molecule has more energy to react
The orientation of the molecules is better
The activation energy decreases
Note: The highest temperature means the greatest rate
Surface area increases rate of reaction because
Note: A powder had greater surface area than a sheet.

3. Introduction: How does each factor work?
Pressure increases rate of reaction because
The number of collisions increases
Each molecule has more energy to react
The orientation of the molecules is better
The activation energy decreases
Note: The highest pressure means the greatest rate
Concentration increases rate of reaction because
Note: The highest concentration means the greatest rate.

4. Introduction: How does each factor work?
Catalysts increase rate of reaction because
The number of collisions increases
Each molecule has more energy to react
The orientation of the molecules is better
The activation energy decreases
Catalysts lower the activation energy by stabilizing the activated complex.

5. Let’s Try It Out!
Oxygen reacts with the surface of a solid cobalt sample. Provide TWO methods for increasing the rate of this reaction.
Increase the surface area
Increase the temperature
Add a catalyst

6. Let’s Try It Out!
RNase A catalyzes the hydrolysis of RNA into nucleosides in solution at 37° C. Provide TWO methods for decreasing the rate of this reaction.
Decrease the concentration
 Decrease the temperature
Remove the catalyst

7. Your Turn!

8. Your Turn!
As the concentration of reactants in a liquid sample increases, the rate of the chemical reaction increases because
Fewer particle collisions occur
More particle collisions occur
The required activation energy increases
The concentration of the reactants increases

9. Your Turn!
As the pressure of a chemical reaction in the gas phase is increased, the rate of the reaction increases because
Fewer particle collisions occur
More particle collisions occur
The required activation energy increases
The concentration of the reactants increases

10. Your Turn!
Why can an increase in temperature lead to more effective collisions between reactant particles and an increase in the rate of a chemical reaction?
The activation energy of the reaction increases.
The activation energy of the reaction decreases.
The number of molecules with sufficient energy to react increases.
The number of molecules with sufficient energy to react decreases.

11. Your Turn!
At what concentration will NaOH and HCl react the most quickly?
0.1 %
1 %
5 %
15 %

12. Your Turn!
At a given temperature and pressure, which 8.0-gram iron sample will react fastest with dilute sulfuric acid?
Lump
Bar
Powdered
sheet metal

13. Your Turn! Given the reaction: Na + 2 H2O → 2 NaOH + H2
At which temperature will the reaction occur at the greatest rate?
-5°C
0°C
45°C
90°C

14. Your Turn! Given the reaction: N2 (g) + 2 O2 (g)  N2O4 (g)
At what pressure will the reaction occur at the greatest rate? (Note: “atm” is a measure of pressure)
0.1 atm
1 atm
2 atm
5 atm

15. Your Turn!
Proteins naturally break down in water, but each bond has a half-life of years. Trypsin is an enzyme that catalyzes the breakdown of proteins, reducing the half-life to 15 minutes. The rate of reaction increases because
The concentration of protein increases
The activation energy decreases
The temperature of the reaction increases
The pressure of the reaction increases