High-school notes - Journal of Chemical Education (ACS Publications)

High-school notes. Elbert C. Weaver. J. Chem. Educ. , 1940, 17 (7), p 346 ... Published online 1 July 1940. Published in print 1 July 1940. Learn more...
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HIGH-SCHOOL NOTES ELBERT C. WEAVER Bulkeley High School, Hartford, Connecticut

CURRICULUM COMMITTEE MEETS

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I X members of the Cnmculum Committee of the American Chemical Society, including Chairman Martin V. McGill, met in Cincinnati on April 710, 1940. Deliberations of the Committee included ID wavs of increasing membershiu in the American ~ h e m i i aSociety l among high-schoil teachers; (2) discussion of the effect of decreased enrolment in definite science courses in secondary schools and the growth of generalized science courses; (3) maturing of plans for the summer courses sponsored by the Division of Chemical Education to be given a t Western Reserve University, June 17-July 26, 1940: (a) Workshop in Chemistry (a list of minimum essentials was presented for discussion by Dr. N. D. Cheronis, a member of the Committee, and general plans were drawn by Dr. R. D. Reed, who will teach a t Western Reserve University this summer); (b) Demonstrations and Projects of High-school Chemistry (a list of topics to be covered was presented by Dr. Reed). Recent additions to the membership of the committee include Dr. R. D. Reed, New Jersey State Teachers College, Montclair, New Jersey, and Mr. T. A. Nelson, Decatur High School, Decatur, Illinois. HEAT TREATMENT EPFECTS

"Bobby pins" or hair clips which can usually be garnered from the girls in a chemistry class are suitable steel for showing heat treatment effects. The wire is straightened and heated in a Bunsen flame until the color is uniform. Svddeu quenching in a beaker of water makes hard steel so brittle that a very short piece snaps in the fingers. Slow cooling in air nroduces a-- soft nliable wire. Restoring the orieinal temper is an interesting test of skill.

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a sensitive test. Cinnabar ore heated in a Bunsen flame produces a definite shadow, as does warm air blown over an open dish of elementaty mercury.ERNESTA. JUST, Polytechnic High School, Long Beach, california, INQUIRY

Who has a simple lecture demonstration to show valence? Law of combining gas volumes? An equilibrium?

I am of the opinion that the mechanical energy put into the spring goes off as excess thermal energy when the wound spring is dissolved. This excess thermal energy may be due to increased inter- or intra-molecular activity. Furthermore, I do not believe that we could measure this energy, because the excess amount of heat given off is so very small. As an illustration of this point: if we do 100 ergs of work on the spring in winding it, in order to get the heat which this spring can produce we must divide 100 by -€he mechanical equivalent of heat, 4.18 X lo'. The quotient, expressed in calories, is a minute immeasurable quantity. Therefore, the spring gives up its potential mechanical energy in a minute amount of thermal energy.-JACK ALESRNICK, 755 South Twelfth Street, Newark, New Jersey.

A BIOGRAPHY OF LOMONOSOV GLENOLA BEHLING ROSE Penns GmvG, New Jersey

SUGGESTIONS

Under the title "Life of Lomonossove, the Celebrated Move the electrodes in the ordinary open wire-light Poet of Russia," there is a short biography in Panorama, bulb conductivity tester closer together. Hold in con- 149-56 &ondon, 1807), writtenin ~ ~ ~by l ~ i ~l h ~ tact with them a piece of glass tubing which has been ~ ~ ~ t~t~ doesf not i agree ~ ~in .all biographical statesoftened in a Bunseu flame. The conductivity of fused mentswith smith or Menshutkin, but it adds nothing salts is thus demonstrated ~u~c~~Y.-ELBERT C. of importance for the chemist. It gives no details conWEAVER, ~ulkeleyHigh School, Hartford, Connecticut. cerning Lomonosov's scientificwork, merely mentioning A fluorescent screen can be made cheaply by coating a that his scientificachievements especially in mineralogy piece of white paper with boot grease (which may be and chemistry were so great tbat his "country will forpurchased from Sears, Roebuck and Company). When ever be indebted to him for the progress of science." illuminated by light from a mercury-vapor lamp, the vapors of mercury show against this saeen as a shadow, 1 J. CHUM.EDUC.,17, 96 (Feb.. 1940). 346

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