JUNE, 1952
QUICKIES ELBERT C. WEAVER Phillips Academy, Andover, Massachusetts
(1) A single lumber match demonstrates (1) low kindling tip, (2) bulb burns even when blown, (3) destructive distillation, (3a) burning of vapors with a flame, (4) burning of untreated crimped end, (4a) burning of a solid. (2) Saturated calcium acetate solution and ethyl alcohol, 5/45 by volume, form a jel that resembles Sterno. Both can be burned. (3) "Pass-around" samples for class purposes can be kept in transparent plastic boxes that once held cheese, etc. Wide-mouthed food jars from home make excellent and inexpensive gas-collecting jars. (4) A student is called to the front of the class. A non-disturbing quick push on the shoulder illustrates the burning of gasoline-air mixture with a knock. A similar push, but with "follow-through," illustrates the burning when catalyzed by tetraethyl lead.
(5) Bunseu burners show the flame profile by scorch pictures. (6) Gas from one burner is carried in the hands to a lighted burner, ignited, and returned quickly to light the original source of gas. (7) A model bunseu burner made of glass shows flame structure, luminous flame, and strike-back. (8) Oil mixed with water quickly separates, but soluble oil mixes with water and forms a permanent emulsion. (9) A bobby pin (hair clip) heated and chilled slowly loses its temper. One heated and chilled by quenching in water becomes very hard and brittle. (10) A froth-flotation mixture makes a permanent exhibit. (11) Aluminum powder shows its hazard as a cause of dust explosion when sprinkled at a flame.
