Table 5 Relationship Between Temperature Of Ion Selective Electrode And Theoretical Slope; Table 6 Relationship Between Temperature Of Calcium Ion Selective Electrode And Theoretical Slope; Impact Of Temperature - ABQ Industrial Horiba Scientific LAQUA 6583S-10C Instruction Manual

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Impact of temperature

The potential gradient measured by the ion electrode method is impacted
by the temperature of the sample solution in accordance with the Nernst
equation. The higher the temperature is, the larger the potential gradient is.
The lower the temperature is, the smaller the potential gradient is.
The standard solution in calibration and the sample solution in
measurement shall have almost the same temperature. Match the
temperature as close as possible.
Theoretical
slope
The optimal way to minimize the impact of temperature on the
measurement of the Ca
between the temperature of the standard solution in calibration and the
temperature of the sample solution in measurement to ±1°C.
The following table shows the change in the potential gradient of the
calcium ion selective electrode depending on the temperature.
Temperature
[°C]
0
10
20
25
30
40
50
62
Table 5 Relationship between temperature of ion
selective electrode and theoretical slope
Unit: mV/decade (mV/concentration change of 10 times)
Monovalent
54.20 56.18 58.16 59.16 60.15 62.13 64.11
ions
Divalent
27.10 28.09 29.08 29.58 30.07 31.07 32.06
ions
2+
concentration is to reduce the difference
Table 6 Relationship between temperature of calcium
ion selective electrode and theoretical slope
Theoretical slope of calcium ion selective electrode
Temperature (°C)
0 10 20
[mV/decade]
27.10
28.09
29.08
29.58
30.07
31.07
32.06
25 30 40 50