A Dead Stop End Point titration is a type of amperometric titration which
makes use of two identical electrodes (usually made of Platinum) with a small
potential difference between them.
The first titration of this type was carried out by Salomon in 1897, but the
method only came in general use after it was rediscovered in 1926 by Foulk and
Bawden.
During these titrations the current is measured as a function of the degree
of neutralization. At the end point the current is zero, and depending on the substances
present in the solution, the current is sometimes also zero before or after the
equivalence point. The proper explanation of these titration curves has long been a
major difficulty. Only in the last two decades it was realized that there is a relation
with electrode kinetics. A current can only flow if both components of a reversible
oxidation - reduction couple are present in the solution in which the electrodes are
immersed.
In this paper the polarization curves of reversible and irreversible redox
couples are briefly discussed. After that it is demonstrated how the different types
of titration curves can be derived from these polarization curves.
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