I have phosphate buffer that is pH 6.9-7.2 that I bring to pH 8.5 with hydroxide. The problem is that overnight the solutions saturate with CO2 and the pH drops to around 6.5 (the pKa of carbonic acid). I was considering using another buffer component, such as carbonate to hold the higher pH, thinking that added CO2 will now be less able to reduce the pH....any suggestions, experience or comments on this? The chemistry can't be altered too much, so I can't use exotic buffer components such as tris.
2006-09-08
05:34:28
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5 answers
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asked by
Robert L. D
2
in
Chemistry