Right, so I'm doing A2 OCR Chemistry coursework right now, and am evaluating an experiment with two methods to find the formula of hydrated iron(II) sulphate crystals. One was a standard heat-a-crucible-full-of-the-stuff jobbie, and I'm fine with the many possible procedural errors and improvements with that, but the other is a titration, and I'm not too sure of any improvements that could be made to the titration procedure. I had thought about some equipment that could tell when the solution had changed colour, thus letting you know when to stop adding to it, but I'm not sure if there is even such a piece of equipment? Any other ideas would be great too. Thanks.