Temperature-Dependent Equilibrium with Cobalt in Isopropanol
Description Two mixtures of isopropanol and 0.2 M cobalt chloride are mixed in a 50:50 v/V ratio. The mixture is heated until the color of the liquid changes to a deep blue. It is then cooled and returns to a pale red color. A second tube is heated until the blue color appears, and then silver nitrate is added. The chloride in the mixture precipitates, and the pale red color will return.
Source: Maynard, James
Year: 2019 Vol: N/A Page: N/A
Keywords: Equilibrium, Complexation, Cobalt, Temperature
Rating: 
Hazard: Some
- Use of mildly toxic reagents
- Chemicals that may be sensitive to the environments
- Corrosive to metals
- Serious eye damage
- Eye irritation
- Specific target organ toxicity- single exposure- CNS
- Acute toxicity hazard- oral
- Respiratory sensitization
- Skin sensitization
- Skin corrosion hazard
- Germ cell mutagenicity
- Carcinogenicity
- Reproductive toxicity hazard
- Short-term (acute) aquatic toxicity
- Long-term (chronic) aquatic toxicity hazard
- Use of hot plate or open flame
Effectiveness: Good
- Results are observable without guidance
- Good connection from demo to course material
- Mild are observed by audience
- Time to results is medium
Difficulty: Low
- Simple manipulations for most to perform
- Demo do not involve deep attention
- Simple procedures
Safety Precautions:
- Eye protection required
- Gloves required
- Hot gloves required
- Lab coat recommended
- Tongs recommended
- Avoid exposure to dusts, mists, vapors
- Perform in a well-ventilated area
- Use UL approved three-prong plug and outlet
- Avoid release of reagents to the environment
Class: Equilibrium
Division: General Chemistry
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