Mn+ 298 K 308 K 318 K
Comp. log K1 log K2 log K1 log K2 log K1 log K2
AAS Mn2+ 5.00 4.20 5.18 4.37 5.37 4.56
  Co2+ 5.18 4.37 5.35 4.53 5.47 4.71
  Ni2+ 5.24 4.43 5.41 4.58 5.52 4.75
  Cu2+ 5.44 4.61  5.62 4.79 5.70 4.90
               
PAAS Mn2+ 7.44 6.41 7.67 6.63 7.89 6.82
  Co2+ 7.63 6.59 7.85 6.78 8.06 6.98
  Ni2+ 7.72 6.65 7.91 6.86 8.13 7.07
  Cu2+ 7.95 6.87 8.14 7.07 8.35 7.26
Table 4: Stepwise stability constants for ML and ML2 complexes of AAS and PAAS in 20 % (by volume) ethanol-water mixture in the presence of 0.1 M KCl at different temperatures.