Post on 30-Nov-2015
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Chapter 13: Titrimetric Methods: Precipitation Titrimetry
CHE 321: Quantitative Chemical AnalysisDr. Jerome Williams, Ph.D.
Saint Leo University
Titration Basics
• Titrimetry includes a large group of analytical methods based on determining quantity of known concentration required to react completel with analyte.
– Volumetric Gravimetric– Coulometric Redox– Amperometric Spectrophotometric
Titration Basics
• Know the following terms.
– Standard solution (titrant)– Back titration– Equivalence point– End point– Titration error– Indicators
Primary Standards
• A primary standard is an ultrapure compound that serves as the reference material for a titrimetric analysis.
• Requirements for Primary Standards– High Purity Modest Cost– Stable Absence of hydrate water– Soluble Large Molar Mass
Standard Solutions
• A standard solution used in titrimetric analysis will be
– Stable– React rapidly with analyte– React completely with analyte to see end points– Undergo selective reaction with analyte that can be
described by balanced equation
Standard Solutions
• Overall accuracy of titrimetric analysis limited by accuracy of the concentration of standard solution used in analysis.
• Two ways to determine concentration – Direct methods– Standardization
Titration Curves
• Two types of titration curves routinely encountered in titrimetric methods; they are sigmoidal curve and linear segment curve.