Reactivity of Alkanes vs. Aromatic Compounds
Description: A mixture of bromine in carbon tetrachloride is added to ungraduated cylinders, one containing pentane(l) and one containing benzene(l). Both cylinders change to a red-orange color upon mixing. High intensity light is directed through the mixture in each cylinder. After several seconds, one of the solutions is made clear and colorless as a result of the light after undergoing a photolytic substitution reaction. The other solution remains unchanged.
Source: UW Card Catalog
Year: 1992 Vol: N/A Page: N/A
Keywords: Substitution Reaction, Bromine, Aromaticity, Photolysis
Rating: 
Hazard: High
- Flammable liquids
- Acute toxicity hazard
- Carcinogenicity hazard
- Specific organ toxicity- Central Nervous System
- Inhalation hazard
- Skin corrosion hazard
- Aspiration hazard
- Aquatic toxicity hazard
- Germ cell mutagenicity hazard
Effectiveness: Good
- Results are observable without guidance
- Good connection from demo to course material
- Time to results is very low
- Reliability is high
- Counterintuitive effects are observed
Difficulty: Medium
- Some careful manipulations required
- Use of toxic reagents
Safety Precautions:
- Eye protection and gloves required
- Downdraft hood or fume hood required
- ABC fire extinguisher on hand
- Spill kit on hand
- Avoid exposure to vapors, mists, gases, or droplets
- Prevent release of reagents to the environment
- 10% sodium thiosulfate solution on hand
Class: Types of Organic Reactions, Photolytic Substitution
Division: Organic Chemistry, General Chemistry
Home| Organic Chemistry Demonstrations| General Chemistry Demonstrations