Titrimetric Analysis - Concepts

Introduction

• basis of titrimetry. Definition of equivalence point, titrant, titration reaction, endpoint.
• types of tritrimetry. Classification by titration reaction. Classification by dispensing method (i.e., volumetric, weight, coulometric). Classification by endpoint detection method.
• direct and indirect titrations. Back titrations and replacement titrations. Advantages of indirect titrations.

Methodology

• general procedure. General formula to calculate amount of analyte in the sample.
• requirements for titrimetric analysis. Sources of error in titrimetric analysis.
• standardization of titrant. Primary standards.

Titration Curves

• shapes of titration curves. Linear and sigmoidal curves. "Sharpness" of titration curves, and its importance
• examples of titration curves: acid-base, argentometric, EDTA, redox titration curves.
• factors affecting titration curve sharpness. Effect of analyte/titrant concentration, equilibrium constant.
• titrant curve calculations: general procedure. Calculation of pH during acid-base titrations.

Methods of Endpoint Detection

• importance of endpoint detection
• classification: chemical and instrumental endpoint detection
• chemical indicators. Three common modes of operation, with examples. Considerations in choosing an indicator, especially for acid-base titrations. Effect of conditions on accuracy and precision of endpoint detection using chemical indicators.
• common instrumental methods for following the progress of a titration reaction. General theory of operation -- especially potentiometric detection -- and shapes of titration curves from these methods.
• comparison: instrumental vs chemical endpoint detection