Sulfur and Iron Reaction

Mixture of iron and sulfur glows under heating.

Scientific name: Iron and sulfur react exothermically.


Sulfur and Iron Whistle 2

by ChemPics

Reaction of iron with sulfur

by ChemToddler

Mixtures and compounds

by nuclearrabbit

Chemistry experiment 49 - Whistling Test Tube: reaction between sulfur and iron

by koen2all


Wear eye protection goggles and gloves.Perform this experiment in a well ventilated room.

Always follow general safety recommendations. Please note that conducting chemistry experiments you must comply with the relevant legal procedures in your country.

Reaction formula

Fe + S → FeS

Step-by-step instruction

WARNING! This experiment is dangerous! You should NOT perform this at home. ONLY carry out this experiment, if you are a trained chemist, and you understand local safety and legal requirements, which are required to perform such experiments

  1. Prepare а mixture of powdered iron and sulfur in weight ratio 7:4.
  2. Put some glass wool to the test tube opening.
  3. Fix the test tube on a stand.
  4. Gently heat the test tube with a gas burner.
  5. The mixture starts to glow.

Scientific background

When the test tube is heated sulfur melts and the reaction between the components begins:

Fe + S → FeS

Iron (II) sulfide is produced. This reaction is highly exothermic. Energy is released in form of light and heat.


Published on 30 March 2015

  • Fire
  • Heating with fire
  • Explosion
  • Poisoned gas
  • Organic
  • Electricity
  • Solution
  • Oxidation reduction
  • Color change
  • Precipitate
  • Gassing
  • Catalyst