Modification of Nanoclinoptilolite Zeolite with Hexadecyltrimethylammonium Surfactant as an Active Ingredient of Chromate-Selective Membrane Electrode

Table 5

Effect of pH on Nernstian behavior of the chromate-selective electrode (−log 𝐶 = 5–2; 𝑛=5) at 25°C.

pH	Slope (mV·decad^−1)	𝑟^2
2	33.9 ± 1.0	0.9880 ± 0.0171
4	41.4 ± 1.3	0.9811 ± 0.0116
6	43.7 ± 0.8	0.9955 ± 0.0073
7	29.8 ± 0.6	0.9905 ± 0.0054
8	29.3 ± 0.4	0.9940 ± 0.0041
9	28.6 ± 0.9	0.9900 ± 0.0057
10	29.5 ± 0.3	0.9926 ± 0.0049
11	19.3 ± 1.6	0.9854 ± 0.0123