Chemistry Teachable Tidbit Summer Institute Randy, Brandi, Casey, Matt, Teresa

Teaching Tidbit Context Our audience consists students in the second semester of a general chemistry course. Typical Units Unit 1 – Intermolecular forces and Solutions Unit 2 – Kinetics and Equilibrium Unit 3 – Thermodynamics

Learning Objectives 1.Generate a model that describes a dynamic equilibrium system 2.Compare and contrast concentration versus time graphs for an equilibrium system 3.Generate an equilibrium expression for a reaction given the rate law expressions 4.Relate the individual rate constants to the equilibrium constant expression Learning Goal Students will understand and appreciate the relationship between kinetics and equilibrium.

t=0 min t=10 min t=20 min Concentration Change over time Imagine you are in your chemistry lab completing an experiment. Your reaction has run for 20 minutes and you have the above data. Each beaker above shows the concentrations of A and B. As a Group 1.Draw a correctly formatted graph showing the change in concentration of A and B over time. 2.Predict: Draw the reaction beaker at t = 30 minutes. Reaction: A B

t=0 mint=10 mint=20 mint=30 mint=100 min Concentration Change over time You then allow your reaction to go for up to 100 minutes. Modify your graph to include the new data. Discuss the change of concentration of A and B over time. Reaction: A B

t=0 mint=10 mint=20 mint=30 mint=100 min Concentration Change over time As the reaction progresses, focus on the black outlined molecule converting between A and B. 4.Discuss within your group whether the reaction has stopped at 20 minutes. At 100 minutes? Reaction: A B

At equilibrium, which of the following statements is true about the rates? A.Rate of forward rxn > Rate of reverse rxn B.Rate of forward rxn = Rate of reverse rxn C.Rate of forward rxn < Rate of reverse rxn D.Rate of forward rxn =0, rate of reverse rxn = 0 Reaction: A B Dynamic Equilibrium

1. Consider the kinetic data produced by monitoring the reversible conversion of Molecule A to Molecule B over time. A B a)Propose a balanced chemical equation to explain these data. b)Generate the equilibrium expression for your proposed chemical reaction. c)What concentrations would you expect for A and B at equilibrium? Assessing Learning Objective 1 - Generate a model that describes a dynamic equilibrium system SUMMATIVE ASSESSMENT #1 (High level HOC)

Reaction: A B 2. a) For the reaction below, circle the graph that best describes the change in concentration over time where K eq = 2.0 b) Explain the reasoning behind your choice. A B Concentration Time Concentration Time Concentration Time Concentration Time SUMMATIVE ASSESSMENT #2 (HOC) Assessing Learning Objective 2 - Compare and contrast concentration versus time graphs for an equilibrium system

Reaction: A B 1.Using the Graph above: a.What time are the concentrations of A and B equal? b.What time has the reaction reached equilibrium? SUMMATIVE ASSESSMENT #3 (LOC) A B Concentration Time Assessing Learning Objective 1 - Generate a model that describes a dynamic equilibrium system

Inclusive Teaching Strategies 1.Engage more learning styles by: using visual, auditory and tactile learning opportunities 2.Engage more personality types by: working in small groups asking one group member to report out 3.Make material accessible to include more abilities by: simple diagrams without “scary molecules” color choices for teaching materials Normal Color VisionRed-Blind/Protanopia Vision