horiba 5002S-10C, Instruction Manual

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57
Reference
C
haracteristics of ammonia
electrode

Measurement range
The range where linearity is established between the logarithm of the ion
concentration and the electromotive force is called the measurement
range.
In general, the range for measuring ion concentration using ammonia
electrodes is a maximum of around 1

10
-1
mol/L and a minimum of around
1

10
-6
mol/L to 1

10
-5
mol/L.
Furthermore, when lower concentration is measured where the linearity is
not established, perform calibration at two points in the lower concentration
range.
Fig. 7 Calibration curve of ammonia electrode
Linea Linearity is not seen.
Linearity is seen Linearity is seen.
150
100
50
0
-50
-100
-200
-150
0.01 0.1 1 10 100 1000
Electromotive force
[
mV]
Ammonium ion consentration [mg/L]
Ammonium ion concentration [mol/L]
1×10
-6
1×10
-5
1×10
-4
1×10
-3
1×10
-2