Homework Problems

1.) Calculate the optimized geometry of Methyl Bromide, using unrestricted Hartree-Fock with a basis set of 6-31(d).

2.) Calculate the optimized geometry of 1,2-Dichloroethane.

3.) Consider the isomerization of 2,5-dihydrofuran (DHF) to 2,3-DHF:

a. Determine the value of for this reaction at room temperature and atmospheric pressure.

b. Determine the value of at the same conditions.

c. If a container is initially loaded with pure 2,5-DHF at 298 K and 1 atm, what will be the final (equilibrium) mole fraction of 2,5-DHF?

d. If the container's temperature is subsequently increased to 600 K, what will be the final (equilibrium) mole fraction of 2,5-DHF? Assume that ideal gas conditions apply.

4.) Consider the following reaction, which occurs through a classical SN2 mechanism:

a. Is this reaction exothermic or endothermic? What is the value of at 298 K and 1 atm pressure?

b. Use transition state theory to estimate the value of the activation energy for this reaction.

c. Now consider the case where all the H atoms are replaced with F atoms in both the reactant and product. What is the for this case?

d. Explain why the activation energy for the F-substituted case would be different. (HINT: There are at least two possible factors that can come into play. Consider the Mulliken atomic charges to come up with one of them.)

More will be coming soon...