For a school science project I'm testing the solvent powers of various cola products (and one non-cola carbonated soda). Finding out whether there's a difference between diet & non-diet, etc.
I've tried to set up the experiment as fairly as possible: I have a set of old pennies ranging from 1950s to 1960s and I'm going to weigh them beforehand on a scale that's accurate to 10 milligrams, leave the coins in various liquids (out of Coca Cola, Coke Zero - sugar free, Fanta - cola free, and purified water as a control) for 8 hours, then weigh them again afterwards. I'll use identical glasses, keep them in the same place (out of the sun to ensure that the heat doesn't speed up any reactions), and the same amount of each liquid (125mL). I'll also repeat the experiment to ensure reliability.
I need some background information prior to doing my experiment. Could the artificial sweeteners in the diet soft drink affect it? What about the carbonation of the water? Should I have another control with just carbonated water? That kind of thing.
Thanks for your help. Any additional sites or books I might be able to read would assist greatly.