Study Set Content:
Assay of Sodium Chloride Injection
Titrant
AgNO3
Assay of Sodium Chloride Injection
Indicator
DCF, TS
Assay of Sodium Chloride Injection
Visual End poinnt
Pink color, NaCl
flocculates
Type of Assay
Fajan Method or
Direct precipitation
Method
Assay of Theophylline Injection
Analyte
C7H8N4O2; 1,3-Dimethylxanthine
(mEq: 0.1802)
Assay of Theophylline Injection
Titrant
AgNO3 and NH4SCN
Assay of Theophylline Injection
Indicator
Ferric Ammonium Sulfate TS
Assay of Theophylline Injection
Visual End point
Black ppt (Ag2S)
Assay of Theophylline Injection
Type of Assay
Volhard Method (Indirect precipitation method/residual method)
Based on the oxidation reduction reactions between the analyte and the titrant.
REDUCTION – OXIDATION ASSAYS
Sometimes a reactant or an analyte has a strong color that an additional indicator is not
needed.
Sometimes a reactant or an analyte has a strong color that an additional indicator is not
needed.
KMnO4 solutions can be standardized easily and retains its concentration over long periods of time if it's protected from sunlight and entry of organic matter
Permanganate Method (Permanganometry)
can be standardized easily and retains its concentration over long periods of time if it's protected from sunlight and entry of organic matter
KMnO4
It also serves as its own indicator
(distinct pale pink color).
Sample Assays:
H2O2 solution (direct)
Malic Acid in Cherry Juice (indirect)
K nitrite, Na nitrite, Pb monoxide (residual)
direct procedure
Iodimetry
The reversible reaction 2I ↔ I2 + 2e can be applied in analysis of reducing agents such as thiosulfates and arsenites by the use of standard solutions of iodine.
Iodimetry
indirect procedure
Iodometry
the sample of oxidizing agent is reduced with excess potassium iodide and an equivalent amount of iodine is produced. Iodine formed is titrated with a standard solution of sodium thiosulfate.
Iodometry
Both methods use what as an indicator
Starch TS as indicator
