Summary: A puddle of glycerol is poured on a pile of potassium permanganate in a porcelain cup. After about 30seconds, the reaction bursts into purple flame.
Hazards:
Potassium permanganate is a strong oxidizer.
Chemicals and Solutions:
15 g potassium permanganate
2-3 mL glycerol
Materials:
porcelain dish
Procedure:
Place KMnO4 in dish
Add glycerol on top of potassium permanganate
Stand back. After 30 sec. the reaction mixture will burst into a purple flame
If larger crystals of potassium permanganate are used the reaction is much slower. (For this reason you can use this demonstration while teaching kinetics.)
Hint:
This reaction can be delayed if the crystal size of the potassium permanganate is large.
Discussion:
The reaction:
14KMnO4 + 4C3H5(OH)3 ----> 7K2CO3 + 7Mn2O3 +5CO2 +16H2O
To schedule a demonstration, please send an email to the demonstration lab.
Contact:
Eric Camp
Lecture Demonstration Technician
Bagley Hall 171
(206) 543-1606