Introduction

Aluminum dust added to finely ground I2 produces heat and copious purple vapor upon the addition of water.

2Al(s) + 3I2(s) →2AlI3(s) + ∆

Supplies

Short List

  •   Evaporating dish (60mm in diameter)
  •   Distilled water in wash bottle

Chemicals

  •   Aluminum dust
  •   Iodine crystals (grind iodine crystals with mortar and pestle to fine powder)

To Conduct Demonstration

  1. Place evaporating dish on a ventilation grate on the bench.
  2. Place finely ground iodine crystals and aluminum dust in the evaporating dish and mix with a stirring rod.
  3. Carefully add a few drops of water from a wash bottle.  CAUTION: Do not breathe any of the fumes!

Demo Time: ~5 minute

Safety and Disposal

Intense heat and vapors are produced in the demonstration.  Perform only with adequate ventilation.  Handle hot glassware with care.  Do not breathe aluminum dust.