Form groups to include students who had investigated Reaction A and Reaction B in the BCE.

1. Compare the chemical equations that describe the overall reaction that occurred in Reaction A and Reaction B.

2. Compare the mechanisms that describe the overall reaction that occurred in Reaction A and Reaction B.

3. Using the data from Question 4 in the BCE compare the rates of Reaction A and Reaction B.

4. In Reaction B

a) does R fulfil the characteristics of a reactant in the overall reaction? Explain.

b) does R fulfil the characteristics of a product in the overall reaction? Explain.

c) does R fulfil the characteristics of an intermediate in the overall reaction? Explain.

d) What are the characteristics of R in the overall reaction? In the mechanism of the reaction? Explain.

 

Figures I and II depict Reaction Coordinate diagrams. Which Reaction Coordinate diagram best describes Reactions A? Reaction B?

Label the reactants and products in both diagrams. Estimate the activation energies for Reaction A and B.

Based on the activation energies for the two reactions how do explain the difference rates. How do the differences in the mechanisms for Reaction A and B

Construct an explanation that you could use to explain to another group the chemical characteristic of R and how R effects the rate of a chemical reaction. Use some or all of the following terms in your explanation: reactants, products, intermediate, catalyst, activation energy, reaction mechanism, alternative reaction pathway, increasing rate, decreasing rate, activated complex, exothermic, endothermic, enthalpy change, early step of a mechanism and a subsequent step in the mechanism, connections between the the overall reaction, the mechanism of a reaction and the reaction coordinate diagram for a reaction.

Clicker Questions: Show a mechanism and ask students to identify reactants, prducts, intermediates, catalysts, etc.