Table 2.

Nickolsy–Eisenman coefficients for ions found in soil.

Chemical (ppm)	Concentration	Concentration and Salt Used	${\mathit{K}}_{\mathit{A},\mathit{B}}^{\mathbf{POT}}$ for ISE	ΔE for RE (mV)
Sulphate	20 ppm	0.2 mM Na2SO4	−0.087	−0.67
Sulphate	96 ppm	1 mM Na2SO4	−0.019	−4.33
Chloride	35.5 ppm	1 mM NaCl	0.064	0.33
Nitrite	30 ppm	0.65 mM NaNONa2	0.086	−0.67
Ammonium	10 ppm	0.55 mM NH4Cl	0.012	−0.67
Potassium	600 ppm	15.3 mM KCl	0.317	−2.33
Magnesium	400 ppm	16.5 mM MgCl	0.004	3.67
Phosphate	20 ppm	0.2 mM Na3PO4	0.074	2.00
Chloride	5300 ppm	150 mM NaCl	0.002	2.67
Calcium	3000 ppm	75 mM CaCl2	1.377	12.67