"Fiery rain" experiment
How to obtain the pyrophoric iron
In this simple experiment you will see that depending on the size of particles, you can even set fire to iron!
Reagents and equipment:
- iron(II) oxalate dihydrate;
- test tube;
- gas burner;
- test tube holder;
- cotton wool;
Heat the iron (II) oxalate dihydrate in the flame of the burner until its color changes from yellow to black. Sprinkle the contents of the test tube on cotton wool soaked in acetone.
Pyrophoricity is the ability of a solid material to self-ignite in a powdery state. The powders of several metals have these properties, for example. When iron(II) oxalate dihydrate is heated, iron, carbon dioxide and water are released in the breakdown reaction. And the iron that is released has pyrophoricity.
FeC₂O₄ · 2H₂O = Fe + 2CO₂ + 2H₂O
As soon as the iron particles come into contact with the oxygen in the air, they burn, forming iron oxides.
10Fe + 7O₂ = 2Fe₂O₃ + 2Fe₃O₄
Pyrophoricity is a serious problem in industry, where fine powders are used.
Wear protective glasses. Observe safety rules in working with fire and flammable items and substances.
Warning! Only under professional supervision.