Table 14–2: Potential of the Ag/AgCl reference electrode
Cl
-
(mmol/L)
E
Ag/AgCl
dE (mV)
a
3500
190
0
2500
199
8
1500
212
21
500
240
49
100
280
90
20
321
130
10
338
148
8.0
344
154
6.0
351
161
4.0
361
171
2.0
379
189
1.0
396
206
0.5
414
224
a. Rounded to the nearest whole number
A salt bridge Ag/AgCl reference is loaded with saturated KCl and the ISAAC is in contact with the
concentration of chloride added to the mobile phase. dE is the potential difference compared with
EAg/AgCl in saturated KCl (3500 mM Cl-).
14.1.5.3.2 Restriction using ISAAC
The restrictions using ISAAC is mentioned below:
• A high working potential (> 1.2 V vs. Ag/AgCl in 2 mmol/L KCl) will oxidize Cl-, which then
contributes to background current and noise.
• In ion chromatography, the addition of Cl- may lead to undesired chromatographic changes.
• When using a silver working electrode, the addition of Cl- to the mobile phase will cause
formation of an AgCl coating on the working electrode, leading to inactivation.
• At high pH or high modifier concentrations, the HyREF is more suitable.
14.2 General precautions
Note the following precautions before you assemble the flow cell:
1. The flow cell is assembled properly when it arrives. Ensure that all marked items on the
checklist are included.
December 16, 2021, 715007395 Ver. 00
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