Table 1.

Effect of dissolution reaction on suspension pH following addition of 4.7mg L⁻¹ MoO₃ in NP water adjusted to pH 9.98 based on the hypothesized stoichiometry (Eq. 1), experimental data and MINTEQ modeled values. Measured pH data was obtained as the average of 3 triplicate experimental replicates. The agreement in estimated N_H+ values between the three methods provides support for the product identification (molybdate) and reaction stoichiometry hypothesized in Eq. 1 (2 moles H⁺ per mole MoO₃ dissolved).

Method	pH change during dissolution	Apparent moles of protons generated by dissolution reaction, NH+ (μmol/L)
Eq. 1 prediction (for 4.7mg L−1 MoO3)	n/a	98.6
Direct pH measurement	9.98 → 5.5	98.7
MINTEQ modelling of pH change in an open system	9.98 → 5.4	99.4