Orange Tornado
Description: A precipitate of mercury iodide is formed in the vortex of a stirred solution of a potassium mercuro-iodide. The precipitate may be dissolved and reformed by adding excess iodide ion or mercury (II) ion.
Source: Shakhashiri, B.Z. Chemical Demonstrations: A Handbook for Teachers of Chemistry
Year: 1983 Vol: 1 Page: 271
Keywords: Complex ions, Precipitates, Equilibrium, Mercury (II)
Rating: 
Hazard: High
- Acute toxicity hazard – oral, dermal, inhalation
- Specific organ toxicity – nervous system, thyroid
- Electric shock hazard
- Aquatic toxicity hazard
- Reproductivity hazard
- Serious eye damage
- Skin irritation
Effectiveness: Average
- Results are observable with guidance
- Somewhat conceptually connected to course material
- Moderate failure rate
- Time to results is high
- Mild effects are seen by audience
- Primary effects are observed
- Fine manipulations
Difficulty: High
- Multiple-step procedures with varying results depending on order or amount of reagent addition
- Use of toxic reagents
- Demos requiring practice or training to perform safely and correctly
- Simple manipulations for most to perform
Safety Precautions:
- Eye protection required
- Gloves required
- Use UL approved three-prong plug and outlet
- Absorbent materials on hand
- Avoid exposure to dusts, mists or droplets
- Perform in a well-ventilated area
- Perform in a chemically resistant surface
- Prevent release of reagents to the environment
Class: Aqueous Equilibrium and Precipitation Reactions
Division: General, Inorganic Chemistry
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