Page 24 - Pharmaceutical Analytical Chemistry II - Pharm D- 02-06-07102

• Completeness of the reaction

The change in the equivalence-point region of redox titration (magnitude
of end point break) becomes larger as the reaction becomes more
complete.

(↑ difference in E0 of the sample and titrant), the more complete is the

reaction.
At least a 0.2 V difference is required for a sharp end point

The redox titration is feasible if the difference in E0 of the redox couples

(sample and titrant) is ≥0.2 V

Detection of the END POINT in redox
titrations

The equivalence point in the redox titration curve is marked as the
steepest point occurs at the rising part of the curve ---- it is
characterized by abrupt change in Esys

End point detection:

• Visual indicators
1. Self-indicators
2. Specific indicators
3. Redox indicators
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