BURNING WITHOUT ACCESS TO AIR Submitted by:
Voldemar Alfthan, Helsinki, F i a n d Cheeked by:
PREPARATION
Provide 0.1 g KRlnOnon a watch glass, pure alcohol, conc H2SOl, one %in. Pyrex test tube, a small funnel, a 50-ml beaker, and a 400-ml beaker half filled with water at 50°C.
Dale Dreisbach, Hiram College, Hiram, Ohio
Observe the flashes and small explosions that occur at the boundary of the two liquids. After a few minutes add another small portion of the permanganate to the tube to cause a new series of flashes.
DEMONSTRATION
CAUTION
Clamp the test tube at a 60' angle. With the small funnel introduce conc HzSOato a height of 3 cm in the test tube. Pour pure alcohol slowly along the wall of the tube to form a layer of about 6 cm. Carefully turn the tube into a vertical position, avoiding any mixing of the two layers. Drop a few crystals of KMnO, into the test tube, cover the tube with the small beaker, and warm the mixture by lowering the tube into the beaker of warm water.
Do not use more than 0.1 g of KMnOd and do not add it too rapidly. A safety shield is recommended. Be certain the reaction has ended and the contents of the test tube have cooled before pouring into a large quantity of cold water. REMARKS
The permanganate in the presence of sulfuric acid furnishes the oxygen necessary for the rapid combustion.
