The ChemBytes website has a sophisticated set of learning resources for chemical equilibrium. Simulations and practice problems are integrated to help students understand the basics.
So, it’s helping to bed down analysis, problem solving, doing the sort of detective work to get to an answer. And the students also seem to quite enjoy having material presented to them in that way - here’s a spectrum, what do you think the structure is, because it’s a more active form of learning as well. So I find I enjoy teaching it, and they respond well in terms of, they keep coming in and asking me for additional problems to practise on which is clearly evidence that they feel it’s challenging them.
I think it’s a key teaching topic, also because it’s teaching students to look at data and to interpret data, to assess which part of that data is going to get them to the answer and which part is exquisite detail that they can come back to later on.
It’s continuous learning. I mean, what I used to try to say to students when I taught the acid-base stuff I’d say ‘look there are only about six types of problems and if you can solve one of them you can solve them all because they’re all the same.’ But what you’ve got to be able to do is look at the question and say to yourself ‘this is one of those types of questions therefore this is the way I should think about approaching it.’ So take the question, dissect it, decide what you’re being asked to do, decide what information you’re given, and then say ‘yeah that’s one of those types of q
We teach way too much stuff. We teach way too much stuff that we used to teach because students didn’t have the resources available to them that they’ve got now. I mean if you look at the resources - they’ve got textbooks, they’ve got electronic media, they’ve got Sapling. They can do the problems in their own time in a guided way with something like Sapling.
If you look at the resources - students’ have textbooks, they have electronic media, they have Sapling. They can do the problems in their own time in a guided way with something like Sapling. All we as lecturers have to do is give them the framework to solve the problems. If you set up the framework for them and let them go away and use that framework and learn how to solve problems they’ll teach themselves. So it’s a matter of giving them that framework and it’s the buffers that are the framework of it all.
Ask the students to look at structures and consider what charge different parts of the molecules will have when they are protonated and deprotonated (eg. COOH to COO- is neutral to negative, and NH3+ to NH2 is positive to neutral, but can have OH groups that become O- sometimes, depending on the pKa). Use a table of amino acid structures and pKa values, and get them to work out charges at the pH of interest.
Photocopy the problems rather than expecting students to download them from Blackboard, and take in only a few copies so that students have to share. They’re forced to work together. But that causes a problem at the end of the class if they all want their own copy, so you then have to go back and load it up onto Blackboard. But that sort of approach works quite well.
Get the students to present the solutions to NMR problems, with a bit of assistance. Point to a signal on the spectrum and say ‘have you thought about what that means?’ Give them some hints. Encourage the students themselves to be asking the questions about what the signals are or why you ignored a particular signal.
