Question

4.   Draw a free energy reaction coordinate diagram for both a generic endergonic and a generic exergonic reaction (label each). Make sure to label the x- and y-axes. Now label where reactants and products should go on the figure. Draw something that illustrates the free energy change for each reaction. Now write something like the following next to your figures: “reactants <—> products”.  

a. What do the reaction coordinate diagrams have to do with the text you just wrote?  

b. What is represented by the graphs that is not represented in the text?  

c. Which of the two reaction coordinate diagrams represents a thermodynamically spontaneous reaction?  

5. Return to the diagram you drew in #4 and do the following. Start with the endergonic reaction. Add the term “K_eq" (equilibrium constant) above the arrow in the text “reactants <—>products”. This constant is defined as: [products]/[reactants], or the ratio of the product concentration to reactant concentration at equilibrium. Do the same for the exergonic reaction. Now for each reaction write whether K_eq is greater than, less than, or equal to one. If you don’t know the answers, look them up, ask TAs, or ask the instructor.

6. Use your figure from exercise #5 to make predictions about what would happen to both endergonic and exergonic reactions if (a) they were to start at equilibrium and (b) either reactants or products are added to or removed from them. We’ll return to these figures for the next lecture so don’t trash them.  

Answer 1

Answer 2