Expert Insights

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. We don’t have to do it, all we’ve got to do is give them the framework to solve the problems.  And I think we often misunderstand how much we should give them because I think we underestimate the value of letting them solve problems in a guided way with things like Sapling.  And I think, you know, in the old days we’d just do problem after problem after problem, which is as boring as anything.

You could identify people and you use it in a constructive way.  But if you could show some identity, that you’re not a remote person up the front, that the big class is not anonymous, it just helps to break down that barrier.  And once they trust you and once they like coming, that solves a lot of other problems - behavioural problems, learning problems and so on.

I think it’s really important that people mark assessments.  Mark, and see what the students actually end up knowing.  Because they can pretend to themselves that students have understood everything, but if they actually have to mark the exam papers, or the quizzes, or whatever it is, they actually are confronted with the students actual knowledge.  I think that’s really influential.  The second semester of teaching, when you think you’ve explained things well, and then 90% of the class have not got it, then it’s not the students fault at that point, it’s probably your fault.  So I think that assessment is really important.  Not only for the students, but also for the marker.  I think you can learn a lot from marking.

Ions and ionic chemistry are essential to life and just about everything they will run across.

I think for a lot of people, before they started chemistry, especially if they haven't done any chemistry before, they've got no real understanding of the difference between macroscopic things and microscopic and atomic sized things. We all know how important that distinction is.

Too often I think students and others think that analytical chemistry is just that measurement step.  When you use the AA, when you use the ... and doesn’t take into account, well all of the other stuff, what’s the actual problem you’re trying to solve?  What are you actually trying to do, sampling, measurement, validating your results? Because only then when you’ve got a result, only then does it actually become information.

Students from high school might understand that vinegar for example is a weak acid compared to hydrochloric acid, but they never knew why. And you could then show them that with equilibrium, this is why. And all of a sudden they’re, 'oh, I’ve always known that I shouldn’t spill HCL on my hand, but I can spill vinegar on my hand and put it on my fish and chips'... Those sorts of moments can really... the students go ‘oh wow.’

Anonymous

It is vitally important for their understanding of chemistry that they understand that molecules are three-dimensional things and that they have a spatial requirement in that they have a shape of their own and that shape will change.  They can't do higher level manipulations without an understanding of three-dimensional nature of molecules.

When you think of things in terms of energy you can represent energy … energy can be modelled as a particle, as matter.  It can be modelled using waves and then trying to talk about how we would use each model as it's appropriate for a particular situation.  It's the sort of things we observe might dictate which model we use to explain it, by recognising that in each case there is another model but perhaps just not as useful.  So maybe it goes back to just trying to show that everything that we do is a model, every model has its upside and its downside and that we usually only use a model that’s as detailed as it needs to be for the particular concept that you're trying to get across.  If you want to get across a concept of a car to someone who has never seen a car you don't probably show them a Ferrari or a drag racing car.  Maybe you show them a Lego style block and we do the same thing with our scientific models as well.  I guess trying to get across that idea that this is the model that we're going to use but it can be a lot more complicated.  I don't want you to think it's as simple as this but it's appropriate under the circumstance.  So I guess I spend a lot of time talking about things as models when I'm talking about quantum mechanics.  Our treatment in the first year, which is where I cover it, a little bit of second year but I don't take a mathematical detail treatment of quantum mechanics.  Someone else does that, so I really bow to them. So most of mine is non-mathematical, just simple mathematics and mainly conceptual type of stuff.  I guess some of the things I try and do to illustrate the differences between the models and the way that we use them is to ask questions in class that might be postulated in such a way that you can't answer it if you're thinking about both models at the same time.  So the one I like is where I show say a 2s orbital and the probability distribution of that node in between.  I talk about things that … there's one briefly, this plum pudding model which they all laugh about.  When you look at this 2s model there is a probability and a high probability, relatively so, that the electron can be inside the nucleus, if you think about it in particle terms.  Then talk about the nodes and so on and how they arise in quantum mechanics and so on and then ask questions like if the electron can be here and here but it can never be here how does it get there?  ...  I try and get across maybe the bigger picture, everything we're going to do from this point on (because we do this fairly early in first year)  - everything is going to be a model.  Nothing is going to be right.  Nothing is going to be wrong. Nothing is going to be exactly the way it is.  Everything will be just a model. You'll hear us saying things like ‘this is how it is’ or ‘this is what's happening’.  But really you need to interpret that as ‘this is a model and this is how this model is used to explain this particular phenomenon.

And it’s so essential, if you are in the middle of a discipline, to have a really well developed sense of what your colleagues around you are teaching, so that you can make connections.

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