Fig. 5 State Of Liquid Junction Of Reference Electrode - Horiba Scientific 6560S-10C Instruction Manual

Mechanism with which the reference electrode maintains a
stable potential
Fig. 5 State of liquid junction of reference
electrode
The internal solution in the reference electrode is discharged to the sample
solution or standard solution as a mechanism of generating such a stable
potential. The stable potential with almost no change, V0, can be
generated by the diffusion of the outflow of the internal solution into the
sample solution or standard solution.
If the internal solution in the
reference electrode is not
discharged, the ion concentration
cannot be measured accurately
because the reference potential
may change depending on the
sample solution or the standard
Tip Tip
solution.
It happens if the amount of the internal solution in the reference
electrode is insufficient or the rubber stopper is not opened which
does not make the internal solution exposed to the atmosphere.
The reference electrode generates the
potential that is used as the reference
against the potential measured with the
V ≈ 0
ion selective electrode. That potential
needs to be stable with very little
variation no matter what kind of sample
solution or standard solution is present.
V
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