Electrical Conductivity of Liquids and Solutions
Lecture Size Breath Alcohol Test
Reaction of Potassium Metal with Bromine
Reduction of Copper Oxide by Hydrogen
Using Large Glass Cylinders to Demonstrate Precipitation Reactions
Coin-operated Red, White, and Blue Fountain: Reaction of Nitric Acid and Copper
Conductivity of Acetic Acid-Water Mixtures
Effects of Ion-Exchange Resin on Conductivity
Oxidation of Chloride Ion by Permanganate
Reaction of Aluminum with NaOH
Lecture Size Breath Alcohol Test
Description: A small amount of ethanol is poured into a balloon, and the balloon is blown up. When the ethanol vapor is released into a large tube containing orange acidified dichromate on silica gel, the ethanol reduces the dichromate to green chromium (III).
Source: Chem13 News
Year: 1997 Vol/No. 261 Page 1
Keywords: Ethanol, Balloon, Dichromate, Chromium (III), Chromium (VI)
Rating: 
Hazard: High
- Oxidizing solids
- Skin corrosion hazard
- Acute toxicity hazard – oral, inhalation, dermal
- Serious eye damage
- Respiratory sensitization
- Skin irritation
- Germ cell mutagenicity
- Carcinogenicity
- Reproductive toxicity
- Specific target organ toxicity – single exposure respiratory system
- Flammable liquids
Effectiveness: Average
- Tenuous connection to course material
- Results are observable without guidance
- Mild effects are seen by audience
- Moderate reliability
- Time to results is medium
Difficulty: Medium
- Multi-phase experiment
- Some intermediate steps to results
- Coordinated manipulations required
- Prior training recommended
Safety Precautions:
- Eye protection required
- Gloves required
- Perform on a chemically resistant surface
- Perform in a well-ventilated area
- ABC fire extinguisher on hand
- Spill kit on hand
- Prevent release of reagents to the environment
- Avoid exposure to droplets, mists, and dusts
- Prevent exposure to open flame
Class: Redox Reactions
Division: General
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