I think what I try to get students to see is that we use models and you use a model, while it works. Then when it doesn’t work you develop a more sophisticated model, and what we’re doing now is developing a more sophisticated model of the structure of the atom, of bonding between atoms. So they find that difficult, the fact that you’re putting aside the model you used previously and developing a more sophisticated one. I think that’s something, it just knocks their confidence a bit.
The difference between chemistry as it happens in a flask, chemistry as we show it on paper or in a textbook and helping students to understand that these are representations and they're conceptual frameworks that we use to understand our discipline and so helping them put those two pieces together.
I like to approach chemistry as a different language, because it used symbols to convey ideas across, but they are not the reality. When we draw a little stick structure, alcohol does not exist as I’ve just drawn it, it’s a representation.
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 t
Use large scale diagrams with many molecules to show the progression from initial to reacting to equilibrium, and extend that with changes to the system that influence the equilibrium. In these ensure that there are many molecules present rather than one.
Use little cartoons or even just physical representations. Have a jar of marbles representing electrons and move them around. Because sometimes having physical things to manipulate helps with understanding of a concept. Even though in reality it’s nothing like it, it’s just a representation.
Try to show students that the fundamental form of matter is energy. Then that this can be represented as particles with mass or as waves (wave functions). Then try to show them that we use the model particle/wave that best helps us understand different phenomena. In class I often do this by asking questions about wave mechanics in particle terms. eg. If a 2s orbital has a node how can the electron pass accross it? Then explain to them the limitations and advantages of each approach.
