value cited in the abstract as weighted average log K, in table 2: 7.974!, in text and table value obvious exchanged with log K (Na), log K (0.1M NaNO3)= 7.992, log K (0.01 M)= 7.888, and log K(0.001 M)=8.023 , data sets of all ionic strength were taken together in calculation: log K=7.975