Table 2: Precision of the potentiometric method for GEMI determination.

Concentration Taken (-log C) Found (-log C) Recovery % ± RSD*
1 × 10-3 M 3 2.988 99.6 ± 1.12
5 × 10-5 M 4.3 4.356 101.3 ± 1.26
1 × 10-6 M 6 6.023 100.38 ± 1.74

*values are mean of three determinations; RSD = (SD /mean*100).