Thursday, December 12, 2013

Good luck on the final!

And remember...

Thursday, December 5, 2013

Exam revision

Here's some more practice problems for you to try: one exam from 2010, and another compilation from earlier than that (note: there is an error in Q38, the formula should be C4H8O, not C4H10O.

I recorded myself solving the compilation. The picture is a little fuzzy and the sound not great, but if you get stuck on a particular question and want to know how I got the answer, just skip through the video until you find it. I went through problems at roughly 1/minute. I circled the wrong answer in Q4 AND Q7 (the answers are right in the key); sorry! See how easy it is to make silly mistakes when you're rushing?

Dr Briggs reports that answers to old exams are not posted for any course. I am of course happy to answer any questions you have during the review session, office hours, etc.

Tuesday, December 3, 2013

Exam, review sessions, office hours

Important info about the final.

There will be three review sessions. They are all open to any Chemistry 101 students.

Tuesday December 10 - 10:00am to 11:30am in Bob Wright Sci B150 (Dr. McIndoe)
Wednesday December 11 - 10:00am to 11:30am in MacLaurin A144 (Dr. Briggs)
Thursday December 12 - 10:00am to 11:30am in MacLaurin A144 (Dr. McIndoe)

My remaining office hours are Dec 4, 5, 6, 9, 11, 12 from 3-4 in Elliott 307.

Good luck!

Sunday, December 1, 2013

iClicker registration

A few of you have not yet successfully registered your iclickers:

Students in Section A01 (MR 1300):
agillesp aheiter ashkan bythesea cmhof daximos denders dhewison fjgirard freemanj giannott halajian halleon hwikim kieras krix liamp luked moniquej moseszvs ncotejac pilatop ryderhoy sshtein tallaric theeruha wallis wkuun wootton4 xcsolis

Students in Section A02 (TWF 0930):

amyllyko ankitas aturvey chishiki dcporter dhamelin elianab iainreid jasmine1 mackaybr mattbian megancht mfdoom nagisa86 nishado pji raunaq rsdale 

If your NetlinkID appears on the list above, please go here to register your clicker. That will match up the responses you've already given this term with your clicker to your student ID.

Thursday, November 28, 2013

Chapter 7

Any questions on Chapter 7 material? Ask them here.

Saturday, November 16, 2013

Midterm practice

We went over some old midterm questions in class on Thursday/Friday. Here is a copy of the 2011 second midterm (and here is the answer key). I highly recommend you try these out, along with the practice midterm posted on the course website.

Thursday, November 7, 2013

Chapter 6

Any questions on Chapter 6 material? Post them here.
Note: Dr Fraser Hof will be teaching material from Chapter 6 in the week starting November 18. I will still be running my office hours as normal that week.

Thursday, October 31, 2013

Chapter 5

Any questions on Chapter 5 material? Post them here.

Tuesday, October 22, 2013

Additional reading

For chapters 2, 3 and 4. Don't forget about trying the MasteringChemistry assignments for practice!

Chapter 2. Two good sites dealing with the Periodic Table are WebElements and Visual Elements. Physic2000's take on the Periodic Table. Tutorial: The Periodic Table.

Chapter 4. Tutorials: VSEPR | Expanded Valence | Hybridization | Bond Dipoles.

Tuesday, October 15, 2013

Chapter 4

Questions on Chapter 4 material? Ask them here.

Wednesday, October 2, 2013

Chapter 3

Any questions on Chapter 3 material? Ask them here.

Those pesky transition metals...

We construct electronic configurations by filling up orbitals in the order we encounter them in the periodic table (you may have learned the Madelung rule in school, i.e.

but we don't teach this because you get given the periodic table)

However, when we REMOVE electrons, we take them from the highest principle quantum number orbital, and this leads to the funny result that for the transition metals, we add electrons to the (n-1)d orbitals but remove electrons first from the ns orbital. If you're happy with this rule, stop reading now. Apply it and you will be fine!

If you're not happy with the rule, good. You're thinking critically, and this rule doesn't really make sense. Surely if the 4s orbital is lower in energy, we should remove electrons from it before the 3d orbital?

Well, in actual fact, it's NOT lower in energy for the transition metals. The increase in Zeff as we move to the right draws in the 3d orbitals more than the more expanded 4s orbital, and it ends being higher in energy:

So what actually happens as we move across the d block is that we add electrons to the 3d orbital first, because it's lower in energy (though it wasn't for K and Ca). So why do we end up with 4s electrons at all? It turns out the energies of the 4s and 3d orbitals are close enough in energy that electron-electron repulsion becomes important. So for Ti for example, the first 2 electrons go into the 3d orbital. The next 2 however can reduce their e-e repulsion significantly by going into the slightly-higher-in-energy-but-much-larger 4s orbital, and they do so. For Cr, the first 5 go into the 3d orbitals, but only one goes into the 4s orbital.

Still confused? For the full story, see

Monday, September 23, 2013

Chapter 2

Any questions on Chapter 2 material? Ask them here.

Sunday, September 22, 2013

Mastering Chemistry assignments

I am getting the same question over and over again on the blog and by email, in addition to addressing it explicitly multiple times in class. Here is the answer again: the ONLY graded assignments are the graded quizzes. Their due dates are as follows:

Graded Quiz 1 - Chapter 1.1, 1.2, 1.3 – Due Wednesday September 18 
Graded Quiz 2 - Chapter 1.4 to 1.9 – Due Wednesday September 25
Graded Quiz 3 - Chapter 2 (all) – Due Wednesday October 9
Graded Quiz 4 - Chapter 3 (all) – Due Wednesday October 23
Graded Quiz 5 - Chapter 4.1 to 4.5 – Due Wednesday October 30
Graded Quiz 6 - Chapter 4.6 to 4.8 & Chapter 5 – Due Wednesday November 6
Graded Quiz 7 - Chapter 6 (all) – Due Wednesday November 27
Graded Quiz 8 - Chapter 7 (all) – Due Wednesday December 4

(taken directly from the course website).
EVERYTHING else is simply for practice, and is entirely optional and for your benefit only. Assigned homework will be reassigned at a later date so you can try it again for revision purposes.

Wednesday, September 18, 2013

Pencast experiment

I have a new gadget - a Livescribe Echo Smartpen. It allows me to record what I'm saying and what I'm writing. Typically, these are used by *students* to record their lecturer; I'm trying it out in reverse. I plan to record solutions to questions that students bring me during office hours, so for those of you who don't have the time can get the same teaching experience as those who do visit me. The explanations of particular problems will be delivered in the form of a playable pdf file, and in today's case, you can hear and see me solving a problem that asks how many photons of microwave radiation does it take to heat up a small cup of coffee. Feedback on how useful (or not!) you find this is most welcome; it's very much at the experimental stage.

Additional reading for Chapter 1

Here are some links you might find useful. In particular, the animated tutorials are a good learning aid; they come from a textbook called Chemistry - the Science in Context by Gilbert, Kirss and Davies and published by WW Norton.
- TutorialsElectromagnetic Radiation | Light Emission and Absorption | Bohr Model | De Broglie Wavelength | Quantum Numbers | Electron Configuration
- has a great online resource called The Quantised World (you'll recognize some of the figures from the lecture book).
- an excellent, if somewhat long, tutorial from Physics2000, on the Quantum Atom. It goes on to Beyond the Hydrogen Atom.
- Check out the Orbitron, a gallery of atomic orbitals and molecular orbitals.
- Breaking Bad - Walt's science lesson
Army of Darkness
Modern materials in the iPhone

Friday, September 13, 2013

Revision for labs

Some tutorials to help you brush up on the basics for your labs:

The FULL ebook - the one you access through MasteringChemistry - also covers all this background, mostly in Chapters 1-4.

The drop-in center on the Elliott landing is a good place to go for help with labs. Here is a link to the schedule; go when Elvis or Monica  are there.

Monday, September 9, 2013

Robin Theron

... is the lecture TA associated with Chem101. You can meet her in the lecture drop-in hours, and she will periodically be commenting on this blog as RobinT. You can regard her answers as authoritative. You may have also noticed Sandy Briggs commenting under his own name, and as course coordinator, his word is of course law!

Wednesday, September 4, 2013

Chapter 1

Any questions on Chapter 1 material? Ask them here.

Thursday, June 20, 2013

Getting ready for Chem101 in Fall 2013

Welcome! I run this blog as a means for students to ask questions of me during the term. You can do so anonymously, but just as importantly (more, from my point of view!) it serves as a kind of FAQ that means I only have to answer questions once (whereas by email or in person, I might have to do so dozens of times). You can actually find this resource useful even if you never ask a question yourself. Previously, I've maintained this blog just for students in my own section; this time, I'm teaching two sections and I will be opening it further still to the whole course (so yes, if you're in Dr Briggs' section, you may ask me questions). All I ask is that you please check first that your question hasn't already been answered!

Occasionally, I will also post links that you may find helpful in your quest for understanding the course material.

How do you ask a question? It's easy - just click on "comments" and leave a note. It should appear on the blog promptly, and I'll generally answer within 24 hours. As the course goes on, I'll invite questions on the different chapters we cover.