horiba 6582S-10C, Инструкция по эксплуатации

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About interfering ions in K
+
concentration
measurement
When a high concentration of cations exists, the potassium ion selective
electrode will be affected by, for example, measurement errors and
electrode drift due to the interference by cations.
The following table lists the cations that cause a 10% error with respect to
the K
+
concentration and their corresponding concentrations.
Table 7 Substances that cause a 10% error in the reading, and their concentrations
If drift of the potential or reduction in the response speed occurs, high
interference by the ions shown in the table is likely to be occurring.
In such a case, soak the potassium ion selective electrode in pure water for
one hour and then soak it in the standard solution for a few hours to restore
a normal state.
Unit: mg/L
Interfering cation
K
+
concentration
1 mg/L 10 mg/L 100 mg/L
Rb
+
0.3 3 34
Cs
+
4 44 443
NH
4
+
12 120 1200
Li
+
70 700 7000
Na
+
230 2300 23000
Mg
2+
240 2400 24000
Ca
2+
400 4000 40000
Sr
2+
876 8760 87600
Ba
2+
1370 13700 137000