If 15 mL of 0.1M HCl titrant is required to reach the Phenolphthalein endpoint and an additional 25mL is required for the Bromcresol Green endpoint, what are the percentages Sodium Carbonate and Sodium Bicarbonate in our original sample? The mass of the sample used was 0.25g.
For this one I don't even understand exactly what I'm trying to find out, and I have no idea what a Phenolphthalein endpoint, or a Bromcresol Green endpoint is.