First off - an apology to all those whose 52s I haven't commented on - I can't believe there are still threads I haven't visited at all, yet, but I will, I will.
Chemistry -

With no handy labs around for test tubes, conical flasks and all the other paraphenalia of school chemistry labs, I really didn't have any ideas for this. But then I remembered being told that Chemistry is at the heart of all matter, and I looked closer to home! In the kitchen, in fact.
I'm the sort of cook who wanders into the kitchen sometime in the evening and peers into the fridge to see what's there and then cobbles something together - a bit of this, a chunk of that and whatever seasoning I think might work. As long as it doesn't take more than half and hour! The only time I measure ingredients and follow recipes is when I'm baking, when the ratio of one ingredient to another seems to be fairly important and each ingredient has a specific job to do. Just like a chemical equation, in fact.
My effort for Chemistry then, is "A Cake Equation":
Each of the four main ingredients has a function:
The flour (which contains gluten) becomes elastic when manipulated with a liquid and becomes semi-rigid when baked. The gluten develoment is affected by the ratio of fat to sugar to liquid.
The eggs trap the air whisked into them, which supports the flour. When the cake's baked the air expands to make the cake rise (hopefully!) They also contribute colour and flavour.
The fat (ordinary block margarine in this case) coats the gluten strands in the flour so the mixture doesn't become tough.
Sugar increases the volume of the mixture when it's creamed with the fat, and (apparently) raises the final coagulation temperature of the gluten within the flour so that the cake has more time to rise. And of course, it adds sweetness.
So there's all this chemistry going on, and I thought I was just baking a cake.
Photographically, the hardest part of this was the pping, and I needed patient telephone support from Ian (irw1) - thanks Ian, I got there in the end!

I'd never really used layers before so this isn't perfect, but it's whetted my appitite to practise and be more adventurous.
Right, I'm just off to put the kettle on - cake anyone?
Jean