Abstract

A flow injection method (FIA) for the determination of hydronium in rainwater has been developed and optimized. The lower limit of detection is 2.7 mumol/L-3O+ and the upper limit of detection is 180 mumol/L H-3O+. The standard deviation in the working range is less then 1.5 mumol/L H-3O+. Comparison with the titrimetric method showed a small difference of -2.1 mumol/L H-3O+. Comparison with the hydronium concentration calculated from the pH showed a significant difference of 3.6 mumol/L H-3O+.