Chloro Complexes of Cobalt (II)
Precipitates and Complexes of Nickel (II)
Precipitates and Complexes of Silver (I)
Spectroscopy in Large Lecture Hall II
Bromo Complexes of Copper (II)
Colorful Complexes Ions in Ammonia
Colors of Complexes of Transition Metal
Iron (III) Thiocyanate Complex Ion Equilibrium
Precipitates and Complexes of Copper (II)
Precipitates and Complexes of Iron (III)
Slow Formation of a Chloro Complex of Chromium(III) Ion
Description A quantity of Hydrochloric acid is added to a sample of 0.01M Chromium (III) Nitrate. The mixture is heated and the solution changes color from a deep purple to a dark green in about 10 minutes of heating.
Cr(NO3)3(aq) + 3HCl(conc) + Δ → CrCl3(aq) + 3NO3-(aq) + 3H+(aq)
Source: UW Card Catalog
Year: N/A Vol: N/A Page: N/A
Keywords: Chromium, Ligands, Substitution, Lability, HCl, Ions
Rating: 
Hazard: Some
- Oxidizing Solids
- Skin irritation
- Eye irritation
- Skin sensitization
- Short-term (acute) aquatic hazard
- Long-term (chronic) aquatic hazard
- Corrosive to metals
- Skin corrosion hazard
- Serious eye damage
- Specific target organ toxicity-single exposure – respiratory system
Effectiveness: Average
- Results are observable without guidance
- Time to results is medium
- Good reliability
- Contrast between systems is noticeable
- Some connection from demo to course material
Difficulty: Medium
- Use of potential carcinogens
- Procedures with intermediate steps to results
- Reactions or demos at non-standard conditions
- Some timed manipulations
Safety Precautions:
- Eye protection required
- Gloves required
- Thermal gloves recommended
- Perform in a well-ventilated area
- Use UL-approved three-prong plug and outlet
- Avoid inhalation or exposure to mists, droplets, or vapors
- Prevent release of reagents to the environment
- Absorbent materials on hand
- Sodium bicarbonate on hand
Class: Equilibrium, Transition Metals and Coordination Compounds
Division: Inorganic Compounds, General Chemistry
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