NAVI F-52 - Page 251

Chapter 16 Reference
16.3 Ion measurement
238 HORIBA
*1: The allowable pH range for the value specified in the parentheses under the measurable
ion concentration.(pH range slightly changes depending on the ion concentration.)
*2: The change in electric potential at the electrode which occurs when the ion concentration
has increased by 10 times.(25 ℃ )
*3: When the concentration of interfering ions has exceeded the value which is obtained by
multiplying the concentration of the measured ions by the allowable coexistence limit, the
electric potential at the electrode is affected by interfering ions and this makes measurement
impossible. (The effect by the coexistence of interfering ions decreases as the allowable coex
-
istence limit becomes larger or the concentration of the measured ion becomes higher.)
*4: The internal liquid types are not limited to the solutions listed in the table. You may use
other internal liquid so far as you have determined that its bleeding rarely interferes or affects
the electric potential at the electrode and less frequently causes electric potential differences
between the solutions.
6582-10C
Potassium
K
+
7682
(1 pc)
① 0.04 to 39000 mg/L K
+
(1 to 10
-6
mol/L K
+
)
② pH 5 to 11
(3.9 mg/L K
+
)
③ -58 mV
Li
+
, Na
+
, Mg
2+
, Ca
2+
,
Sr
2+
, Ba
2+
=more than
1000
NH
4
+
=70
Cs
+
=3
Rb
+
=0.4
(At 10
-4
mol/L K
+
)
3.33 mol/L NaCl
(250 g/L Sodium
chloride)
6583-10C
Calcium
Ca
2+
7683
(2 pcs)
① 0.4 to 40080 mg/L Ca
2+
(1 to 10
-5
mol/L Ca
2+
)
② pH 5 to 11
(4 mg/L Ca
2+
)
③ -29 mV
Na
+
, K
+
, Ba
+
,
NH
4
+
=more than
1000
Mg
2+
, Ni
2+
,
Cu
2+
=1000
Mn
2+
=500
Co
2+
=350
Sr
2+
=50
Fe
2+
, Zn
2+
=1
Fe
3+
=0.1
(At 10
-4
mol/L Ca
2+
)
3.33 mol/L KCl
(250 g/L potas-
sium chloride)