Oxidation States Of Vanadium (II) with Permanganate
Synopsis: Ammonium Metavanadate is dissolved in aqueous solution, as which it has a characteristic clear yellow color in solution. The solution is treated with a Jones Reductor, which changes the color for each corresponding to the oxidation state of the Vanadium complex. The colors changes from yellow to blue, the dark green, and finally, purple. The reduced mixture is then titrated back to a +5 oxidation state using a 0.02M potassium Permanganate solution.
5V+2(aq) + 3KMnO4(aq) + 3H2O(l) → 5VO3−(aq) + 3Mn+2(aq) + 3K+(aq) + 5NH4+(aq) + H+(aq)
Source: UW Card Catalog
Year: N/A Vol: N/A Page: N/A
Keywords: Oxidation state, Reduction, Vanadium, Titration, Permanganate.
Rating: 
Hazard: Medium
- Acute toxicity- oral, inhalation, dermal
- Eye irritation
- Specific target organ toxicity- repeated exposure – inhalation, respiratory tract
- Short-term (acute) aquatic hazard
- Long-term (chronic) aquatic hazard
- Corrosive to metals
- Skin corrosion hazard
- Serious eye damage
- Potential flammability of dusts
- Oxidizing solids
- Oxidizing liquids
- Scalding hazard
- Electric shock hazard
Effectiveness: Average
- Some connection from demo to course material
- Mild effects are observed by audience
- Results are observable with guidance
- Time to results is medium
- Moderate failure rate
Difficulty: Medium
- Use of scientific equipment
- Some careful manipulation required
- Volume dependent addition of reagents for proper results
- Procedures with some intermediate steps to results
Safety Precautions:
- Eye protection
- Gloves required
- Avoid exposure to dusts, mists, or vapors
- Perform in a well-ventilated area
- Use UL approved three-prong plug and outlet
- Prevent release of reagents to the environment
Class: Transition Metals
Division: General, Inorganic Chemistry
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