The first page of every set of lecture notes specifies which exercises correspond to those notes.  You may notice that Exercises 2.1 and 2.2 are not listed for the first set of notes.  This is NOT because they are unimportant.  It’s because they address very important overarching concepts that we use throughout all of our discussions of molecular orbital theory.  So, they don’t really apply specifically to any one set of notes.  They apply to all of them!

That said, some students will find it easiest to start with Exercise 2.3 (which corresponds directly to the first set of notes) and Exercise 2.4 (which corresponds directly to the second set of notes), saving Exercises 2.1 and 2.2 to do next.  But if you ever ask yourself “why is/isn’t that pi?” or “why is that the z axis?”, it’s time to go review Exercise 2.1…

Answer keys are for checking your work. There is little to no value in reading an answer key without first attempting to solve the problem yourself. All that does is give you a false sense of security because every problem looks much easier after you’ve seen somebody else solve it.

Exercises:

Answer Keys: