Fresno meeting hears Seaborg

February 17, and Saturday, February 18. The featured speaker of the meeting was. Glenn T. Seaborg, ofthe University of California at Berkeley. SYNTHES...
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PACIFIC SOUTHWEST ASSOCIATION O F CHEMISTRY TEACHERS FRESNO MEETING HEARS SEABORG HEWITT G. WIGHT California State Polytechnic College, San Luis Obispo, California

A JOINT

meeting of the northern and southern sections of the PSACT was held on the campus of the Fresno State College, Fresno, California, on Friday evening, February 17, and Saturday, February 18. The featured speaker of the meeting was Glenn T. Seahorg, of the University of California at Berkeley. SYNTHESIS OF ELEMENTS 99, 100, 101

Professor Seaborg stated that the first direct evidence that elements 99 and 100 could be synthesized was obtained quite unexpectedly in an analysis of the debris of a hydrogen-bomb explosion in 1952. Samples of the debris from the explosion were collected on large filter papers carried by drone airplanes through the radioactive clouds. The analysis of this debris was carried out a t the University of California Radiation Laboratory, the Argonne National Laboratory, and the Los Alamos Laboratory. The method for nuclear synthesis of these eleme~tsinvolved repeated neutron capture by uranium. Dr. Seahorg *dated that the resulting discovery came as a surprise. The method of analysis of the debris of the explosion exploited the chemical similarities between the trans-

uranium elements and the rare earths. The method of separation made use of an ion-xchange process adaptcd to the separation of very small amounts of material. Work with other transuranium elements had demonstrated their very pronounced chemical similarity to the comspondina rare earth elements. The desien of the experiment was such that any new substances which might be present would he separated, and identification would bs possible. The order of elution of the new elements from the ion-exchange resin was found to be in the reverse order of their atomic numbers, or 101, 100, and 99. To confirm the findings from the debris of the hydrogen bomb, these elements were synthesized by other processes. Using plutonium as the starting material, the atomic weight and atomic number of the material was built up by repeated neutron capture followed by electron emission. A particularly interesting piece of research was the synthesis of element 101 from element 99. About lo9 atoms of element 99 were bombarded with alpha particles. They were placed as a target material on the reverse side of an inert metal support. When a nuclear

Members of the PSACT Attending the Meeting at Fresno State College. February 17-16. 1956

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JOURNAL OF CHEMICAL EDUCATION

reaction occurred, it released sufficient recoil energy to an immediate necessity. He mentioned that one way cause the newly formed atom to be displaced to another to implement this program would be to increase the piece of inert metal properly placed. These atoms of number of available science teachers in the high schools. element 101 underwent spontaneous atomic fission, so One way to do this might be to make considerable the presence of each individual atom could be detected. salary adjustments. As a result of these techniques, the announcement of the ncm element was made after five individual atoms had VARIED PROGRAM OF PAPERS In addition to the address by Professor Seaborg, been isolated, and their fissions observed. The discoverers have suggested that the names ein- there were a number of other stimulating talks. E. steinium, fermium, and mendelevium be used for ele- B. Womack, head of the chemistry department a t ments 99, 100, and 101, respectively, with the symbols Fresno State College, discussed the problems of the junior-college student in transferring to a. four-year colE, Fm, and Mv. Einsteinium was observed to have a half-life of about lege or university. In some cases, he felt that the 20 days, and to undergo alpha emission. Fermium mas junior-college student had not had sufficient laboratory found to have a half-life of 16 hours; it also undergoes experience to place him on a par with students at an alpha emission. Mendelevium has a half-life of about equivalent level in the four-year college. He recoman hour and decays by spontaneous fission (actually mended the addition of a laboratory course in organic its daughter formed by electron capture decays by chemistry to the junior-college programs. An interesting discussion followed. spontaneous fission). Richard H. Eastman, of Stanford University, preU. S. AND RUSSIAN SCIENTIFIC EDUCATION sented to the group the plan for a course for highCOMPARED school teachers under the auspices of the Shell Merit I n discussing the relative state of scientific education Fello~vshipProgram. This is a program conducted in the United States and Soviet Russia, Prdessor Sea- on the campuses of Stanford University and Cornell horg expressed great concern. As a result of converss- University. A special course has been planned to actions that he recently held with leading Soviet scientists quaint high-school teachers with recent developments a t the "Atoms for Peace" conference in Geneva, in sciences and in teaching methods. The proposed Switzerland, and the careful study of the best available course lasts for 10 weeks with an enrollment a t each statistics, he stated that a t the present time about 250,- university limited to 30 individuals who are supported 000 new scientists are being subsidized each year by the by fellowships from the Shell Company. Soviet government. These brilliant young men and Norman Lofgren, of Chico State College, presented women are chosen for intelligence and talent from 2,- thel'Research for a Day" program that has been tried, 500,000 who reach an age to enter schools of higher edu- with considerable success, by Chico State College. cation each year. Young people are given intensive Under this program, interested high-school students in training, so that they will complete four years of chem- the area are invited to spend one Saturday working in istry and three years of physics by the time they the laboratories of the college under the direction of the graduate from the equivalent of our high schools. By members of the chemistry department staff. The proromparison, the national effort that we are making in gram has been successful in stimulating interest among this direction is woefully weak and inadequate. some high-school students in the area. Professor Seaborg feels that a drastically increased T. Bentley Edvard's discussion of summw workshops program for the training of scientists in this country is has alrea.dy appeared in these pages.

PERKIN CENTENNIAL CELEBRATION

DURIXG the year 196G, the entire chemical world is paying trihutc to an inventive genius in the field of science--William Henry Perkin. His research-conscious mind was respansihle for creating the first synthetic dye-mauve-quite hy accident, just 100 years ago, in an attempt to synthesize quinine, a pharmaceutical derivative of great importance to the far-flung British Empire. Perkin's effort was a failure insofar as his objective was concerned, since he obtained some violet crystals instead of quinine. This ocixrrence may not have been the first of its kind, hut the significant feature about it is that Perkin did not lot matters rest at that point. He pursued his experimentsuntil he had the chemical process under control and was able to market the first synthetic dye, known historically as Perkin's Mauve. The centennial of Perkin's discovery will be climaxed hy a celebration during the week of September 10, 1956, at the Waldorf-Astoria Hotel, New York City. The ohservznce is sponsored by the American Association of Textile Chemists and Colorists, directed hy the Perkin Centennial Committee, and is considered to he of such import to leading technical, chemical, and scientific societies concerned with the production or application of color that 27 such organizations and two departments of the U. S. Government have signified their desire to participate in the occasion.