Subject Code/Name: CHM3911 - Advanced physical chemistry Workload: 3 x 1 hour lectures per week
1 x 4 hour labs per week (this goes for pretty much all weeks besides Weeks 1 and 12, at least in the semester I did it)
1 x 1 hour tutorial per week (
optional).
Assessment: Practical work: 30% (consists of 9 Lab Reports)
Various assignments/tests throughout semester (total 30%), such as:
Three Molecular Symmetry assignments (total of 8%, later assignments worth more than earlier ones)
One-hour (midsem-ish) test on Molecular Symmetry (10%)
Introductory assignment on Computational Chemistry (3%)
Online test on Computational Chemistry (3%)
Molecular Spectroscopy assignment (6%)
Final exam: 40%Note: Prac work is a HURDLE REQUIREMENT. You need at least 50% in pracs to pass the unit.Recorded Lectures: Yes, with screen capture. From personal experience, on rare occasions, the video is somehow missing (you still get the audio). Most lectures will be captured accurately though.
Past exams available: Yes, a couple posted on Moodle. The past exams database has some exams, but it appears this unit has undergone changes in the past, so not all of the material may be relevant. The ones on Moodle are relevant to the current course - the only thing to keep in mind is which parts of the course are being assessed on the final exam (more on this later).
No solutions available.Textbook Recommendation: As the course is reasonably diverse in terms of its content, there is no real "prescribed" textbook. Some of the more commonly mentioned suggested textbooks include "
Physical chemistry" by Atkins (9th or slightly earlier editions), and "
Modern spectroscopy" by Hollas (4th or slightly earlier editions). Personally, I found neither to be a compulsory buy, as the lecture notes do a reasonably good job at covering the content. However, if you enjoy learning from textbooks, or like to go more in-depth and have more explanations, then by all means consider using some of the recommended reading.
Lecturer(s):Computational Chemistry, Thermodynamics and Kinetics: Katya Pas
Molecular Symmetry and Molecular Spectroscopy: Don McNaughton
Surface Chemistry and Colloid Chemistry: Alison Funston
Year & Semester of completion: Semester 1, 2014
Rating: 4.2 out of 5
Your Mark/Grade: Unknown at this point.
Comments: This subject can form part of a chemistry major. If you wish to do Honours in chemistry, you need at least one unit from either Physical or Analytical Chemistry, and at least one unit from either Organic or Inorganic Chemistry.
This unit is divided into six major topics, and each lecturer goes through two of them:
Computational Chemistry (Katya)
Katya's section starts off with Computational Chemistry. This begins with a brief introduction to quantum mechanics (it's pretty much all qualitative, and if you have some background in Physics, this will probably be a recap of things for you). Why is this necessary? Because ultimately, there are some reactions in the lab which might be somewhat dangerous to carry out, require expensive materials/difficult preparation or are difficult to accurately gather data from. Sometimes, it's better to model things before trying them in the lab themselves (e.g. drug design). Therefore, it is better to simulate these reactions. In order to do this though, we need to have an accurate description of the molecule's structure and physical properties. And an accurate description of these requires quantum mechanics to be invoked. So that's why we do computational chemistry.
The next few lectures go through things such as potential energy surfaces (basically multi-dimensional versions of the potential energy diagrams you're used to seeing) and how they are computed, why they have the shape they do, how we interpret local minima and maxima on these diagrams, and why they are important. We then go through some of the computational chemistry methods that allow us to correctly interpret these potential energy diagrams, and hence allow us to predict molecular structure and reaction properties.
However, calculating exact properties is very computationally intensive, and in many cases, thoroughly impractical. So we also learn about the various approximations that are made (both to our "energy-calculator" Hamiltonian and our molecule, which is represented in quantum mechanics as a "wavefunction"). We learn some theoretical basis behind the methods, and their strengths and weaknesses, as well as important properties. Throughout this lecture series, there will often be comparisons of various computational chemistry methods. You will get to do these things yourself in the lab component (more on this later).
Thermodynamics and Kinetics (Katya)
Katya's section continues with Thermodynamics and Kinetics. This lecture series touches on the Fundamental Laws of Thermodynamics, an introduction to macroscopic and microscopic entropy, a recap of enthalpy and Gibbs' free energy, and how we interpret these in terms of chemical thermodynamics and kinetics. Some of this will be revision, and if you did Physics, probably all of it will be. We then briefly look at the Carnot cycle as an example of analysing entropy and enthalpy. The derivations of Gibbs' free energy and the reaction equilibrium constant are also shown.
After this, we look a bit more at phase equilibria. Remember those temperature-pressure diagrams for water, which showed the triple point and critical point? We look at them again here, in the context of the Phase Rule, which is a shortcut way to determine how many variables you can change to keep the same phases as you currently have. We also look at phase equilibria for mixtures of substances, in particular liquid-vapour phase equilibria. This is the theoretical basis for separation techniques such as fractional distillation, and now we can see why such techniques are effective (or not). Finally, we look at supersaturated solutions - how entropy changes with phase, and come across the Kauzmann Paradox, which appears to consider a situation where the Third Law of Thermodynamics is broken. It's never been observed (so Physics isn't broken), but we don't actually know why that is so!
Finally, we look at classical nucleation theory, which explains the kinetics (or time-scale formation) of crystals from supersaturated solution. This is then linked to the Arrhenius equation, and shows a great parallel between crystallisation reactions and regular chemical reactions. There's still a bit of QM thrown in at the end, with quantum 'tunnelling' effects showing up in real-life reactions.
Molecular Symmetry (Don)
Don's section starts off with Molecular Symmetry. This is basically an introduction to the various kinds of symmetry molecules can have (which we call 'symmetry elements'). Once everyone is capable of looking at a molecule and determining what kinds of symmetry it has, we then look at classifying molecules by their key symmetry elements (these molecular classifications are called 'point groups'). Also, we notice that we can do symmetry analysis of rotations, translations and vibrations of a molecule, and to things such as molecular orbitals, dipole moment vectors, and polarisability tensors. So why do we do all this stuff? Well, it turns out that with a bit more work, molecular symmetry actually can help us in identifying the structure of a molecule we might not be able to determine by other means. We can use molecular symmetry to predict the appearance (or non-appearance) of an IR or Raman spectrum, and what we should see if the spectra exist. There is actually some mathematical basis behind all of this, as the study of symmetry comes down to mathematical group theory - but you don't need to worry about any of that here. For the mathematically minded, there's also some matrix algebra involved - see if you can spot where it occurs!
Molecular Spectroscopy (Don)
Don's section then continues with Molecular Spectroscopy. Here, we consider three kinds of spectroscopy - microwave (or rotational), IR (or vibrational), and UV-Vis (or electronic). The theoretical basis of all three methods is considered. For example, where you may recall from CHM2922 that the "ball-and-spring" approximation is used to come up with the energy levels observed in IR spectroscopy, we also have the "rigid rotor" model for microwave spectroscopy to predict energy levels. For each kind of spectroscopy, we basically consider the following questions:
1. Which kinds of molecules will appear on this spectrum?
2. Why are the spectral lines separated in the way they are?
3. Why are the heights of the lines the way they are?
4. How does changing the chemical compound being studied affect the spectrum?
5. What other information can we get from analysing the spectrum?
Understanding this, in conjunction with molecular symmetry, really provides a sound basis for understanding spectroscopy of relatively simple molecules.
Surface Chemistry (Alison)
Alison's section starts off with Surface Chemistry. In a way, this area of chemistry gets partly neglected during VCE and earlier Chemistry units. But, if you recall from your high-school days some strange things about "surface tension/surface energy", "spreading/wetting", "contact angle" or "surfactants", then this is what the lecture series is about. It goes into the reason behind surface tension, and why properties of surface molecules are often different to non-surface molecules (which we call the "bulk"). Much of this section (and the subsequent section) is really based on intermolecular forces, so it's a good idea to revise those so you have a good foundation for the section. However, surface tension is also based on energetics. This means that there is some maths involved in working out various surface-tension related properties, and in calculating surface tension itself. There are derivations of the formulas you will eventually use, which require some knowledge of maths/physics (for example, steps in derivations include knowing that Pressure = Force / Area, or that Change in Energy = Work = Force x Distance). These derivations are usually not examinable, however. After learning about surface tension and how to measure it, we consider the role that surfactants play in reducing surface tension, and the formation of micelles at higher surfactant concentrations. Applications of this section include in detergents, oil drilling and flotation. We also learn about how surface chemistry affects the pressure in objects such as bubbles and droplets.
Then, we learn about spreading/wetting on surfaces, and what factors determine whether one substance will spread over another. The applications of this include water-resistant and water-proof fabrics, and glues/adhesives. After this, we learn about adsorption, which is the adhering of one substance onto the surface of another. Once again, we consider the energetics of adsorption and its reverse process, desorption, and look at how the amount of adsorption varies with how much stuff you put in (which is represented graphically by "adsorption isotherms"). We look at several models of adsorption, and their assumptions, the difference between physical and chemical adsorption, and what happens if your surface has lots of little pores on it.
Colloid Chemistry (Alison)
Alison's section concludes with Colloid Chemistry. Basically, a colloid is when you have a system of particles suspended in a (different) bulk medium, except the particles are usually much larger than your average molecule. We learn about why these are actually thermodynamically unstable, and what makes them last for so long. We learn about how we can make colloids, how we can ensure that they don't come together to form large clumps and effectively precipitate out of solution, and how we can break them apart again. We learn about the models that aim to predict the immediate environment around a colloid particle, based on electrostatics and van der Waal's forces (giving rise to an overall potential). Finally, we see applications and examples in emulsions and foams.
Personally, I found this unit to be a reasonably fun unit, once I actually started listening and learning from the lectures. This is probably because I enjoy the idea of Physics (if not the mind-crushingly difficult maths), and I've always liked learning about orbitals and bonding. I must admit that Surface and Colloid Chemistry was not the most fun topic I learnt in high-school chemistry, but if I treated it as a fusion of chemistry and some maths, the learning wasn't too bad at all. Computational Chemistry was a bit dry on its own - but it's nice to apply what you've learnt from the lectures in the labs. I had quite a love/hate relationship with Molecular Symmetry, because I absolutely cannot rotate things in my head, which made each bit of work I had to do on it incredibly painstaking. With each success, however, there came a lot of satisfaction. I also liked Thermodynamics and Kinetics particularly for its derivations and its brief description of the fundamental thermodynamics laws (well, I guess that means I like Physics).
The lecturers were all great at explaining concepts and answering questions. In particular, I liked how Katya interspersed questions throughout her lectures to give them a more interactive feel. Alison also gave little demonstrations during her lectures and asked us to predict what might happen beforehand. Don also went through some worked examples in his lectures. All of this made the overall learning experience better, in my opinion.
I didn't attend any of the tutes (they were held at pretty inconvenient times for me), but in them, you appear to go through questions from a tute sheet related to the lecture material. The tute sheets (and sometimes the answers) are put up on Moodle as well, and they're often a good revision tool for the exam.
Now, for some comments regarding the assessments:
Labs
Workload-wise, the labs aren't actually too different to those found in CHM2922. You'll have to either write up a full lab report or fill in an extended proforma for each prac that you do. I found that I had to spend at least 5 hours on each full lab report and at least 3 hours on each proforma in order to get a decent mark - so make sure you allocate a reasonable amount of time to get these done. Particularly if you're doing other units with experiments and lab reports in them, the overall amount of work each week can really start getting to you. The lab staff are usually more than happy to consider requests for extension if things really do get too busy.
The lab demonstrators themselves are all very competent and helpful - there's nothing really more to say.
Regarding lab work, there are usually two kinds of labs. Computational chemistry labs are done individually and usually see you in the computer lab, using the computational chemistry program GAUSSIAN09 in conjunction with the Monash Campus Cluster (basically a big supercomputer for all kinds of Monash students to run programs on) in order to complete the lab work for the day. Then, you analyse your readouts from the computational chemistry files in order to help you fill out the lab proforma for that experiment. This kind of lab can be very frustrating at times - because omission of a single space in what you type can cause the subsequent results files you get to either record numerous errors, or not give you what you want at all. One thing that I would suggest is to download the copy of GAUSSIAN09 that gets placed on the Moodle page, and save it to your Monash account and your laptop/computer. This means that you can work on the computational chemistry assignments from any computer in Monash or at home, and really increases the time you get to work on those experiments.
Another thing is that at the start of the semester, you'll probably feel like you're basically blindly copying down instructions from your lab manuals with no idea why anything is going on. However, as you learn the principles of Computational Chemistry, things will start to make a bit more sense. So, my advice here is to persevere, and try not to get too violent when stuff goes wrong - your demonstrator is there to help.
"Wet" labs are more like your standard lab where you get/make some sort of chemical compounds, perform some chemistry on them, analyse them, and then analyse the results later. One good thing about these is that the experimental procedure is nowhere near as demanding as more synthetic-based labs. Usually, the most you'll have to do is make up a series of solutions of different concentrations, perform a pH titration, run a series of IR/UV-Vis spectra, take some measurements from a scale, or some simple chemistry like exposing a sample to light radiation, or using a centrifuge to separate components of a solution. That being said, while it is not as intense, it can still be fairly time-consuming, particularly if your experiment has multiple parts in it. Having a good partner really makes work easier and also more enjoyable. You'll still have to write up your own individual lab reports, but discussing things with your lab partner tends to benefit both of you.
Symmetry assignments
The symmetry assignments are designed to reinforce and apply what you have learnt in lectures, by having you perform symmetry analyses on various simple molecules. This kind of assessment starts straight after your first lecture (when you've learnt all the basic symmetry elements and then have to identify them in other molecules), and continues after you learn more (the second assignment has you assigning point groups, and the third one has you finding irreducible representations to ultimately work out the predicted IR and Raman spectra of molecules). If you're not too good at rotating things in your head, this might take a while, but the skills learnt are well worth it, as they are applied again in the 'midsem' test. One thing I did find handy was to look at 3-D structures of the molecules themselves (particularly ones that you can freely manipulate). Also, there's always this
point group database if ever you are stuck. If you put some effort into them, it's usually enough to get a decent mark. Some people find this easier than others, but as you go through and practice, you tend to come up with your own little tricks or procedures for making things easier for yourself.
Symmetry 'Midsem' Test
The Symmetry 'Midsem' Test is a 50 minute test held during one of the lectures. It basically goes through all the symmetry material, which has hopefully been drummed into you by the assignments. While the molecules present on the test might be different, the tasks rarely change - so if you know the procedures to follow, it's just a matter of identifying and implementing them correctly. Early in the semester, Don puts a file on Moodle of some molecules that you can practice your skills on - usually one of these will be on the test paper in some form, so if you can do most of the 'medium' level molecules on there, you should be fine for that part. The main thing to be aware of, however, is time pressure. I knew how to do all the questions on the midsem - I just couldn't get them all down quickly enough, panicked, and made a mistake that ended up costing a bunch of marks. So, it's really important to get some practice, and to really know what your planned procedures are before the test.
Introductory Computational Chemistry assignment
This assignment is basically meant to help you become used to the basic kinds of procedures you will do in your subsequent computational chemistry labs. How this works is that in Week 2, instead of having a normal chem lab, you'll have a tutorial lab where you're introduced to the Monash Campus Cluster and Gaussian09 and how to do really simple things with the program interface. You'll then work through the instructions on a PDF which tells you what to do in order to get the actual assignment done and fill in the associated proforma. The intention is that when you then do your subsequent computational chemistry labs, what you're doing will be less familiar. That being said, it still took me quite a while to understand what I needed to be doing in those labs. Your demonstrators are really a big source of help on this.
Online Computational Chemistry Test
This online test is more of a theory test on the Computational Chemistry material. You get 1 hour to complete some questions (most are multiple choice or matching-type questions). There isn't really much more to say here - as long as you have your lecture notes in front of you and have a basic grasp of what is going on, you should get a decent mark.
Molecular Spectroscopy Assignment
This assignment comes in two parts: The first part is a standard (untimed) online test with a few questions/calculations relating to what you learnt in lectures. You'll then use the numbers from one of the questions (thankfully not numbers that you've calculated, so don't worry about everything being mucked up) in order to make an Excel-based plot of a rovibrational spectrum, and to answer more questions. It's probably a good idea to leave at least a couple of hours to do the second part.
Final exam
This year, there was none of Don's material on the final exam, which thankfully made it easier to revise for. Revising a number of diverse topics comes with its own challenges. Most people found some pain in the revision process, and I can't say I found many people who liked it that much. One of the really good things though, was that one a day close to the final exam, lots of people from the cohort came to uni and basically went through the past exams together! If you can get this going with your cohort, it's a really, REALLY good way for everyone to benefit and help each other learn. The two past exams we were given on Moodle were reasonable guides to what would appear on the final exam, but there were a few other questions in there too (which I assume must have come from the tute material). The exam itself wasn't too bad - most of the questions weren't overly difficult, but there was a fair bit of time pressure, which really caused me to rush at the end. There were a number of questions where you had to draw diagrams/graphs to help with explaining (as well as other questions where drawing a diagram may have helped too). The material is crammable, but you really should try to avoid this, as it just compounds the pain. Particularly in Alison's sections, KNOW HOW TO CONVERT UNITS. For some reason, surface chemists tend to express their quantities in all kinds of units. So know when you have to adjust the units of things, and what units your answer is expected to take! (Yep, dimensional analysis can really point you i nthe right direction for some of the calculation-based questions there.
In conclusion, if you enjoy Physics but dislike the associated maths that comes with it, you have a decent chance of enjoying this unit. If you always liked orbitals, or thermodynamics/kinetics/equilibria, you'll find some interesting stuff here. If you don't really enjoy these things, or don't like having lots of equations in Chemistry, or don't like doing maths that much, then this unit might not be the best fit for you - there's always Medicinal, Inorganic, and Environmental Chemistry units that you might find more enjoyable.