Test for anions in
solution
Organic Chemistry II (Liberty University)
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, Anionic analysis can be conducted through three main methods: Bunsen, Gilreath, and Vogel. The
Bunsen method classifies anions based on the solubility properties of silver and barium salts, color,
solubility of alkali salts, and ease of volatilization. The Gilreath method categorizes anions according to
the solubility of calcium, barium, cadmium, and silver salts. Vogel's approach involves identifying anions
that evaporate when treated with acids and analyzing their reactions in solution.
Typically, the Vogel method is used for anionic analysis. Anions are commonly divided into three primary
groups:
a. Sulfate Group: SO4^2-, SO3^2-, PO4^3-, Cr2O4^2-, BO2^-, CO3^2-, C2O4^2-, AsO4^-
b. Halide Group: Cl-, Br-, I-, S^2-
c. Nitrate Group: NO3-, NO2-, C2H3O2-
Testing for anions in solution:
1. Sulfate Test: Barium salts such as BaSO4, BaSO3, Ba2(PO4)3, BaCr2O4, Ba(BO2)2, BaCO3, BaC2O4,
Ba3(AsO4)2 are insoluble in water under alkaline conditions, while other barium anion salts dissolve
easily. The sulfate group can be separated and identified by adding a BaCl2 reagent. Except for barium
chromate, which is yellow, the other barium salts are white.
2. Test for Reducing Agents
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solution
Organic Chemistry II (Liberty University)
[A+] Page 1
, Anionic analysis can be conducted through three main methods: Bunsen, Gilreath, and Vogel. The
Bunsen method classifies anions based on the solubility properties of silver and barium salts, color,
solubility of alkali salts, and ease of volatilization. The Gilreath method categorizes anions according to
the solubility of calcium, barium, cadmium, and silver salts. Vogel's approach involves identifying anions
that evaporate when treated with acids and analyzing their reactions in solution.
Typically, the Vogel method is used for anionic analysis. Anions are commonly divided into three primary
groups:
a. Sulfate Group: SO4^2-, SO3^2-, PO4^3-, Cr2O4^2-, BO2^-, CO3^2-, C2O4^2-, AsO4^-
b. Halide Group: Cl-, Br-, I-, S^2-
c. Nitrate Group: NO3-, NO2-, C2H3O2-
Testing for anions in solution:
1. Sulfate Test: Barium salts such as BaSO4, BaSO3, Ba2(PO4)3, BaCr2O4, Ba(BO2)2, BaCO3, BaC2O4,
Ba3(AsO4)2 are insoluble in water under alkaline conditions, while other barium anion salts dissolve
easily. The sulfate group can be separated and identified by adding a BaCl2 reagent. Except for barium
chromate, which is yellow, the other barium salts are white.
2. Test for Reducing Agents
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