In their comment on the article by Oakes et al. (J. Chem. Eng. Data20236825542562), Xiong and Wang (DOI: 10.1021/acs.jced.4c00056) suggest that our model parameters are invalid and defend their
parametrization methodology. Their methodology defense rests on the
assertion that the Pitzer model is empirical and that their parameters
were fit to “qualified” data and tested against independent
data. Their claim of invalidity rests upon the supposition that our
model produces alkaline pHs for NaClO4{aq} and NaBr{aq}.
They also imply that isopiestic data, used in part to derive our model
parameters, cannot be used to derive trace activity coefficients.
We refute the claims that our model produces incorrect values of pH
and pHm, that trace activity coefficients cannot be derived
from isopiestic measurements, and that statistically and physically
meaningful Pitzer model parameters involving trace solutes can be
fitted to solubility measurements.