Estimate carbonate n bicarbonate I. A given mixture
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Answer:
I assume that what you're dealing with is something like commercial ammonium (bi)carbonate, so it's got a fairly high natural pH. I would suggest that the first thing to try is a pH titration with dilute acid - you'll need to get the titration curve, so you need a system which will plot the curve for you unless you really have no alternative to doing it point by point. Interpreting the curve will be complicated! you've probably got 3 or 4 titratable species present, so my first thought is to look for the last (lowest-pH) wave, which will probably be bicarbonate -> CO2. Then work back from that to identify the other waves. Be aware that you are likely to have some ammonium carbamate also present: I can't quickly find the pKa of carbamic acid, but it's said to be a rather weak acid. If you've got a clever titrator that finds endpoints for you, it'll probably miss the weaker ones at the first attempt: I'd much prefer to work from the titration curve and identify the endpoints visually.
If you've got the kit, you can try X-ray diffraction to identify what phases are present. If you can find the crystal structures of all the phases present, you can then use Rietveld refinement to quantify them. Having said that, I would use XRD to find out what phases are present and try tpH titration to quantify them.