Scenario 1: A

B 10% per round
A

B 0% per round
1.
Begin with 40 pennies to represent pile A (the reactant pile).
2.
As the pennies “react” they move to another pile, B (the product pile).
3.
The reactants will be represented by student “A” who will pass pennies to student “B” to put in his/her pile, showing the conversion of reactants to products.
4.
Each passing of the pennies will represent one transfer.
5.
Assume that in each transfer, 10% of A will become B. Thus for each exchange, student A will transfer
10% of her pennies to student B. Round fractions of a bean to the nearest whole number.
6.
Continue this exchange for 10 transfers. Record the results in your notebook.
7.
In your notebook number of pennies in pile A vs. round # on the graph. Use a different color/line to plot the number of pennies in pile B vs. time on the same graph.
Scenario 2: A

B 25% per round
A

B 25% per round
1.
Begin with 40 pennies to represent pile A (the reactant pile).
2.
Assume that in each transfer, 25% of A will become B. Thus for each exchange, student A will transfer
25% of her beans to student B. Round fractions of a bean to the nearest whole number.
3.
Simultaneously
25% of what was in pile B will be transferred back to pile A.
4.
Continue this exchange for 10 transfers. Record the results in your notebook.
5.
In your notebook number of pennies in pile A vs. round # on the graph. Use a different color/line to plot the number of pennies in pile B vs. time on the same graph.
Scenario 3: A

B 50%
A  B 25%
1.
Begin with 40 pennies in pile A.
2.
Assume that in each transfer 50% of what is in pile A will be transferred to pile B. Thus for each exchange, student A will transfer 50% of her beans to student B. Round fractions of a bean to the nearest whole number.
3.
Simultaneously
25% of what is in pile B will be transferred back to pile A.
4.
Round fractions to the nearest whole number.
5.
Actually transfer the pennies in each transfer.
6.
Continue this exchange for 10 transfer. Record the results in your notebook.
7.
In your notebook number of pennies in pile A vs. round # on the graph. Use a different color/line to plot the number of pennies in pile B vs. time on the same graph.
Questions:
1.
What is the difference between Scenario 1 and 2? Which scenario would best represent a reversible reaction and why?
2.
What is the difference between Scenario 2 and 3? What is a similarity between Scenario 2 and 3?
3.
How would you describe the state of equilibrium? What is the “equal” in equilibrium?
4.
During which round did Scenario 2 reach the state of equilibrium?
5.
During which round did Scenario 3 reach the state of equilibrium?