The fitted values of b SLR and k SLR,0 are (2.0 ± 0.3)×10 -2 M -1 and (2.5±0.3)×10 -14 cm 2 s -1 , respectively. The positive value of b SLR is attributed to increases in activity coefficients of reactants or/and the stabilization of the activated complex via interactions with surrounding ions. 23,53