VOL.6. NO.5
THE CERMISTRY SWDENT
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W H Y DOES A SUBSTANCE BURN?
Bring the flame of a lighted match into contact with some paper, fine wood shavings, or splints. Notice the, speed with which the substance begins to burn. Can you suggest a reason for the substance igniting? Is there a possibility that fire is transferred from the burning match to the paper or wood? The purpose of this experiment is to help you answer the questions given above. Follow the next part of the work and see if you can answer the questions. Support a piece of sheet metal of good size, approximately 10 inches square, on a tripod. This sheet metal may be provided either by cutting open an ordinary gallon can or using a pie pan such as may be secured a t the 10-cent store. Place a Bunsen burner with a well-adjusted flame under the sheet metal. Use a good-sized flame, being careful that the flame does not play over the edges of the sheet metal. Now place wood splints or fine shavings on the sheet metal directly above the flame of the burner. In a short time the wood shavings will begin to glow and then burst into flames. You must remember that the flame has not been permitted to come into contact with the combustible substance. How do you explain the cause of combustion? When does a substance begin to burn?-Neo-Chanto-Ion, 3, 12 (Feb., 1929).
