|
| Standard Methods |
| 3500-V B |
| Standard Methods Online |
| Descriptive Name: Vanadium by Gallic Acid Method Official Name: 3500-V B. Gallic Acid Method |
| Media: WATER |
| Inorganic |
| Standard Methods Online - Standard Methods for the Examination of Water and Wastewater |
This is a proprietary method.
Please visit the method owner's site for method documentation |
| The concentration of trace amounts of vanadium in water is determined by measuring the catalytic effect it exerts on the rate of oxidation of gallic acid by persulfate in acid solution. Under the given conditions of concentrations of reactants, temperature, and reaction time, the extent of oxidation of gallic acid is proportional to the concentration of vanadium. Vanadium is determined by measuring the absorbance of the sample at 415 nm and comparing it with that of standard solutions treated identically. |
| The method is suitable for potable water samples. |
| |
| The following substances interefere in the test: chromium, cobalt, copper(II), iron(II & III), molybdenum(VI), nickel(II), silver, uranium(VI), bromide, chloride, and iodide. A table in the method lists the concentrations at which they interfere. Because of the high sensitivity of the method, interfering substances in concentrations only slightly above tolerance limits can be rendered harmless by dilution. Traces of bromide and iodide interfere seriously and dilution alone will not always reduce the concentration below tolerance limits. |
| See Section 3020 Quality Assurance/Quality Control. |
| Plastic or glass containers. Add HNO3 to pH <2. See Section 3010 for more details. |
| 6 months (See Section 1060) |
| Less than $50 |
| |
| |