Introduction
- Principles of gravimetric analysis. Types of
gravimetric analysis.
- General procedure for precipitation gravimetry
- Requirements for gravimetric
analysis
- Ideal properties of precipitating reagent. Ideal properties
of precipitate and weighing form.
Precipitation
- Experimental factors that control filterability
of the precipitate.
- Simple model of precipitation: nucleation and particle
growth. Dependence of rates on degree of supersaturation.
- Homogeneous precipitation and its advantages
- Colloidal suspensions. Properties of colloids (briefly).
Coagulation. Washing of filtered coagulates; peptization.
Contamination of Precipitate
- Two main categories of contamination processes:
simultaneous precipitation and coprecipitation.
- Methods to improve
selectivity of precipitation (i.e., to reduce simultaneous pptn).
- Types of coprecipitation. Description of surface
adsorption, mixed-crystal formation, occlusion and entrapment.
- Methods
to reduce or eliminate contamination from coprecipitation.
Advantages and Disadvantages
- Advantages and disadvantages of gravimetry as an
analytical method
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