Chemical Hydra
How to make chemical monster using ammonium dichromate
A chemical Hydra appeared just in time for our Halloween party!
Safety precautions
Do not try this at home! Perform this experiment only under professional supervision.
Equipment and reagents
- 15g ammonium nitrate;
- 3g urotropine;
- 15g ammonium dichromate;
- porcelain cup;
- 1mL kerosene;
- wooden stick.
Step-by-step instructions
Combine 15g ammonium nitrate, 3g urotropine, and 15g ammonium dichromate in a porcelain cup. Add a few drops of kerosene and light with a wooden splint. A Hydra rises menacingly from the depths!
Process description
Ammonium dichromate intensifies combustion and breaks down along with urotropine and ammonium nitrate to release gases. The decomposition of ammonium dichromate yields nitrogen N₂, water vapor, and green chromium(III) oxide. The chromium(III) oxide makes the Hydra green. The large volume of gases, plus the solid oxidation products, are the secret to the mixture’s “hydra-like” behavior. You can find similar safe experiments in the “Chemistry of Monsters” set by MEL Chemistry!