Horiba Scientific 6561S-10C, Instruction Manual

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66
C
haracteristics of fluoride ion
selective 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 ion selective
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. 8 Calibration curve of fluoride ion
selective electrode
200
150
100
50
0
-50
-100
0.01 0.1 1 10 100 1000
1×10
-6
1×10
-5
1×10
-4
1×10
-3
1×10
-2
Linearity is not seen. Linearity is not seen.
Linearity is seen. Linearity is seen.
Electromotive force [mV]
F
-
concentration [mg/L]
F
-
concentration [mol/L]