I Need a Bop on the Head

Forgive me (or not), my chemistry instructors, for I have sinned.

I assigned an incorrect VSEPR structure on my inorganic final. Of all things, why VSEPR? Why? My high school chemistry teacher will be most displeased.

It was supposed to be trigonal bipyramidal (SOF₄, for those who are curious), oxygen at the "horizontal", but for some reason I drew (and said) square pyramidal. And I didn't catch the error during the final! Oh no, it took me until 1 o'clock in the morning to realize this. And now I can't sleep. *Agitated*

Someone, bop me on the head. By now, VSEPR is supposed to come naturally, like breathing. Especially when it's a main group compound. *Glares at self*

Yes, I realize that getting this aggravated over a stupid mistake is in itself stupid. The agitated part of me isn't listening anyway.

Also, there was this one problem I couldn't finish and I ought to work on when I have time: constructing the sigma-bonding hybridized orbitals of the anion of cyclopentadiene. Bond angle is 108^o.

The final itself was actually quite doable. Lewis dots, assigning point groups, the chemistry of carbon versus silicon, some periodic trends, photoelectron spectroscopy, some valence bond theory, some "find the symmetry operations"-type thing, some diatomic MOs (and the effects of ionization on vibrational frequencies), and a polyatomic MO. I had time to check some of my answers! (Now if I only actually *caught* my errors during the time, that would have been nice...)

Now that the inorganic course is over, I feel a little sad (stupid mistakes aside). Can't wait until the next course!

Next up: thermodynamics, analytical chemistry, differential equations. Not necessarily in that order. And miscellaneous little things like laundry.

[Edited]
I got a chance to see my inorganic final and its answer key after differential equations today. Efficient markers, like I said. More stupid errors include (off the top of my head):

• A more highly polarized bond (e.g. C-F versus C-H) takes up less space, by VSEPR, not more
• We all know that the atomic orbital 5d_z2 has two spherical nodes and a donut-shaped electron density in the middle. What I didn't remember is that, right on the x-y plane, that donut hole is just the origin.
• I can't count to 10: 10 AOs give rise to 10 MOs, and I was missing one. It was a nonbonding MO, too!
• Come to think of it, I can't count to 4, either. (Bond order of the system is not what I wrote down). And I didn't read the question properly (they were asking for the bond order of ONE bond not the entire molecule), leading to the loss of two more marks.
• Removing a nonbonding electron from a heteronuclear diatomic (e.g. when oxidizing the molecule) will actually decrease the bond distance, since Z_eff increases.
• The photoelectron spectrum of a alkali metal cation, relative to the metal itself, will not only be shifted up in terms of energy, it'll also be missing one peak because the valence shell is empty!
• Apparently I got disoriented mid-final and thus sketched one of my MOs all wrong (using the p_z orbital instead of p_y as a guide is not a good idea in a non-cubic symmetry)
• Keyword: SiO₂ "networks" (not necessarily "polyhedra")

To my astonishment, I assigned all the right point groups. Something of a miracle, that. (Last time, I literally got 50% of them correct. Um. Yea.)

Incidentally, the hybridized orbitals of the sigma-framework of cyclopentadiene isn't that bad to derive, after all. The numbers are a little ugly though (I don't like working with decimals, so...lots of square roots).