Kinetics- Iodine Clock Reaction

Iodine Clock Reaction

Description: When two colorless solutions are mixed, there is no apparent reaction. After a short time period, the mixture suddenly turns almost black. Variations illustrate the kinetics of the reaction.

Source: Shakhashiri, B.Z. Chemical Demonstrations: A Handbook for Teachers of Chemistry

Year: 1991   Vol. 4   Page: 16

Keywords: Kinetics, Concentration, Reaction rate, Induction period, Clock

Rating:

Hazard: Medium

  • Acute toxicity hazard – oral
  • Skin irritation
  • Eye irritation
  • Inhalation hazard
  • Electric shock hazard
  • Burn hazard
  • Aquatic toxicity hazard – acute

Effectiveness: Good

  • Results are clearly observable without guidance
  • Clear contrast between behavior of systems
  • Time to results is medium
  • Low failure rate

Difficulty: Medium

  • Some sequential or timed manipulations
  • Reaction at non-standard conditions
  • Prior training recommended
  • Procedures with some intermediate steps

Safety Precautions:

  • Chemical gloves required
  • Thermal gloves recommended
  • Use UL approved three-prong plug and outlet
  • Absorbent material on hand
  • Sodium bicarbonate on hand
  • Prevent release of reagents to the environment

Class: Kinetics

Division: General