Reaction of Potassium Metal with Bromine
Description: A small piece of potassium held at a distance in forceps is touched to a small amount of liquid bromine. A vigorous reaction ensues, accompanied by a loud snap.
This demonstration is also available on video and JCE “Chemistry Comes Alive!” Vol. 1 CD-Rom
Source: UW Card Catalog
Year: 1999 Vol: 76 Page: 1311
Keywords: Potassium, Bromine, Exothermic, Ionic
Rating: 
Hazard: High
- Acute toxicity hazard – oral, dermal, inhalation
- Serious eye damage
- Skin corrosion hazard
- Flammability hazard
- Acute aquatic toxicity hazard
- Explosion hazard
- Substances that emit flammable gases when wet
- Target organs: eyes, skin, mucus membranes, lungs, nervous system
Effectiveness: Good
- Results are clearly observable without guidance
- Good connection from demo to course material
- Strong effects are seen by audience
- High reliability
- Time to results is low
Difficulty: Medium
- Demos with some intermediate steps to results
- Use of highly reactive reagents
- Demos that require training to perform correctly
- Some fine manipulations required.
- Sequential manipulations.
Safety Precautions:
- Eye protection required
- Gloves required
- Lab coat recommended
- Vent hood or downdraft hood required
- ABC fire extinguisher on hand
- Avoid exposure to mists, vapors or gases
- Sodium thiosulfate on hand
- Prevent release of reagents to the environment
- Perform on a chemically resistant surface
- Use of safety rod and secondary containment required
Class: Main Group Elements
Division: General
Home| General Chemistry Demonstrations