TEACHING NUCLEAR CHEMISTRY AT NOTRE DAME UNIVERSITY WILLIAM A. HAMILL, RUSSELL R. WILLIAMS, JR., and ROBERT A. SCRULER' University of Notre Dame, Notre Dame, Indiana
BEQINNINQ with the intensive
wartime development tion of the course which might be clmified as nurlenr s 1 , 3 , 4 , 5). of "atomic" energy, the scientific institutions of this p h ~ i c (Items country have devoted a considerable frnrtion of their effort to the study and application of nuclear phenom- COURSE OUTLINE ena. One consequence of this interest hns h e n the 1. The atomic nuclelra Atomic structure; nuclear mss: nuclear comrmoition: appearance of tenrhing and research progmms clmified nuelcar enerpcties; un~tnblenuclei. as Xuclear Chemistry or Rndiorl~emistr?.in the curr l t r m i r n I m a n i ~ c ~ I ~ f i o nn~#o(fc l rW 8 ricula of many universities. These propmams most 2. Ph!pimlnml Pl~vaienlnrorrrtirs of isotonic nurlides: rhemirsl omnerties . commonly consist of thesis research in the field as well 01 i~otapirnurli&-s; ronr~vntmtionof isotopic nuclides. as lecture and lahoratory courses offered to advanced 8. Dn,iwr/rw preporofion owl ~l~I,-cfionoltcn.fnble nuclirlra Detrrtion of uurlunr rndiations. E1li~icnr.yand rrlinhility students. l e s s frequently, this firlcl may he repre01 drtoctinp:drviaes. I'rc~lurlian01 unrtnhle nuclide. sented in the more elcmcntnry chemistry courses. 4. Ntlrlrar rlrmy renrfiona Instruction in nuclenr chemistry nt Sotre Dame T y l r s o i +my; nbsorption of nuclear radiations. Decay takes placr a t both grndoate and u n d e r p d u n t e levels. arl~cmn:gmetic rrlationqhips; rntc equntionr; units and rtatalnrcls. In the first e ~ s eit. is represented by n lerture rourse nnd homhanfd r m d i o ~ hy thesis re~enrch. Un~lergrnduatosreceive elementnry 5. Ntulmr Surlcar crrm section; t y p ( . ~of reaction*; artificial elements; instruction in the lerturr nnd laboratory rourses in nurlrar lisrrion. physical chemistry. 6. Chrmirnl o p m f i m u ~ f a 6 lnrrrki r
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Prinriplw; purification and analysis; artificial elements.
7. Chcmiml umrr~,ucwaofnt,cIm~r~nrfiona
GRADUATE LECTURE INSTRUCTION
Pl~vricnlba~ia:neutron capture: isomeric transition: other
The grnduate-level lecture course in nuclear chemistry consists of some forty-five lectures given in one semester ench year. It is most frequently tnken in the first year of graduate study by stndenk mnjoring or minoring in physicnl and inorganic chemistry. The course serves a9 n survey for those who will emphasize some other branch of chemistry and as preliminary training for students who intend to pnrme thesis research in the field. A puhli~hedversion of thew lectures is a ~ n i l s h l e . ~ In view of the fact that most vadnate students in chemistry have had only the most elrmentnry training in physics, it is neceswry to spend a cnnsidernhle portion of the time prewnting harkground informntion in nuclenr physics which is nrcemwy for undcrstnnding of the chemical phmomenn. A r o m p r o m i . ~must be adopted hetween tlw nerrpait.y for nclrqunte treatment of this portion of the matrrinl and the r1rsiral)ility of giving proper time nnd emphn-is to t h r numnrous rhemical problems. The divisirm of time in our coursr has been approximately equnl l~etweennuclear physirs and nurlenr chemistry, although no ripid segrcgntion of material has l m n attempted. For example, the rhemical and physirnl mnnifrstations of nuclenr maw nrr considered hefore any disrussion cf nuclear renrrnnpment renctions. The outline irlow serves to inilicnte the por-
ICRP~~OIIS.
&cla of nurlmr radiolirms 8. Chmiml and &iml Ilndirtiona and particles; rndintion chemistry; biolopiesl ellrrts: health physics. 9. Applird nurlmr chmirfry Gmhrmistry: isotopic exchnnp; tracer atudien; analytical npplicxtic,ns.
In the port.ion of the course which is devoted to the more truly rhemical phenomena, an attempt has been made to survey ns mnny as possihle of the considerations which arise t h r o u ~ hthe ahility to produce, detect, nnd clist,inpllish 1)rtween nuclear species. The eflrrt of nnrlrnr mms upon chemiral properties, as evi~lencedby chemicnl differences l ~ e t w e nisotopes, receives early considerntion. After n d i w u & m of the methods of produring and detecting unstnhle nuclides, t,he pernlinritirs of rhemical operntions \vit,h suhmicroscopic (tr:rcrr) amounts of the species are discrr~setl. A fnmiliarity with this subject is fundamentnl to many suhsequrnt chrmirnl studies. A description of the chemicnl properties of those elements known only as artifirial nnstahlc nuclidrs is also includril here. The chrniicnl chnnges resulting from nuclear reactions are t,he suhject of considernhle discuasion. On the one hnnd, the cl~emicnlrenctions induced in the atom undergoing the nurlcnr chnnge are discussed. This subjert is sometimes cnlled "hotatom chemistry" nnd is t-ypified hy t,he Szilnrcl-Chnlmers reaction. In cont Present addrem: Cnnisiun Colle~e, BuRnlo, Ncw York. tmst, the study of the chemicnl reactions induced hy 1 WILWALIR, R. R., JR., "Principh of Surlmr Chemi~lry," nuclear rndintions as thry are ahsorhed is usually reD. Van Naqtrand Co., X c r York. 1950. 8
ferred to ns "radiation chemistry." This subject lends naturally to a discuwion of the biologicnl effects of nuclear radiations nnd of henlth physics. The concluding lectures nrr titled ;\pplird Nuclear Chemistry to indicate thnt the subjert mntter is devoted to a survey of the ways in n.hich t,lw techniques of nuclear chemistry can 1% applied 1.0 tlw solution of prohlcms of other hrnnrhes of chemist,ry. r\ Inrm share of the mntrritrl may IE descrilwd I y the phrn..rs "isotopic exchnnge reactinns" and "trawr studirs" and in these rases the sourrr materid is so voluminou~that only n few typical cnnmplrs rnn I* given. 'Tlw mnin ohjcrt, is to lenrr the student with somc appreciation of the cnpnhilitirs of the trzrrer methocl, rathrr than to attempt a criticd interpretnt,ion of the results. This lecture course dnes not nt,tempt to give a complete description of lahorntory pror,dures in either physical or chemicnl considerations, since elementary training of this nature is nvnilnhle in Inhorntory courses and rvlvanced trnining in thesis researrh.
UNDEROWUATE UBOWLTORY INSTRUCTION
Experiments in nuclenr chemistry appear in hoth of our nndergrnduate Inhorntory rourses in physical chemistry. In t,he first course, one afternoon's work (out of a total of twelve afternoons) is performed hy every student. This work ronsists of a study of connting oprration~,including plntcnu dderminntion, statist.irnl flurtuntions, and ahsorption of hetn rnrlintions. The derny of ?.>minute I'za is nl.w obwrved. The wrnnd .semester of physical chemistry laborntory inrludes t h m to five additinnnl periodsof nuclear chemistry, cleprncling on the Rturlmt's inrlinntions. Additional counting considerntions. such ns ~cntteringand dend-time lossrs are studied. Growth of &minute In"' in neutron bombardment and the complex decay of bromine activities are ol)wrverl. In addition several experiments on exchange renct,ion#,using nrtive iodine, are performed. These experiments have l m n described in clrtnil in previons communicntions.' This lnborntory work has l m n specifically designed for use on the undergmdunte level nnd the investments THESIS -FCH of time nncl money h a w I m n minimized. One of the Formal lectnre and Inhorntory tmining in nuclear unique fentures of the work is the 11.w of a 5-mg. Ra-Re chemistry at the grndunte level might well be regarded neutron source t o nctivnte samples for student work. a s sterile unless arrompanierl by nn active progrnm of Among the nclvantngcs of this prwedure is the ability to research in this field. At Sotre Dame four stnff mem- u w short-lived nctivit,ies. This permits activation and bers and approximately fifteen graduate studmts are decay within a single Inlmrntory period and mluces the conducting resenrch in vnrinus phnses of nurlenr chem- prohlem of contnminntion of lnhorntory equipment. istry. The inrliri~laalp r o l h n s fnll lnrgrly into the The henltl~hnrnrrl ussociated with the use of such a genrrnl fields of radintion r l ~ e m i s t psnd hot-ntom chem- smnll source is very smnll nnd the neutron flux ohtnined istry. Alw, swernl npplirnt,ions of rwlioactive t,rncer is of course compnrnldy smnll. However, direct actiterhniques to the kinetic prol)lcms arising in thew and vation of mhstnnces of high cross section, such as inallied fields are now in progrew dium and gold, is quite feasihle nnd nctivstion of This research program cnjo>.rigenerow s u p p r t from wvcrnl other elements may be nccomplishd t,hrough the University and the U. S. Atomic Energy C'ommis- use of the Srilnrd-Chnlmers rcnction.' sion nnd lux- i t s origin in the wartime work of the staff I t m m s incvitnhle thnt experimmts of this type will memlwrs and sevrrr~lgraduate sturlmts with t.110 Plu- find incrensing use in under~rnrluntephysicnl chemistry tonium Project,. I t is rnn~plementctlhy artire resenrch Inhorntory courses. We ferl thnt t.how suggesterl are in nuclenr physics a t the University and fncilitaterl hy approprinte to the ndvancrrl unrlerpm~luatelevel of incontnrts with the Argnnnr Sational l ~ l w r ~ ~ t , in o r y strurtion. S o lnrge proportion of our un~lrrgrnduateor Clicngn, in which Kotre I h m e is R pnrticiprrting uni- grnclunte utudent bocly mny lw expected to find emversity. ployment in the at,omic energy i n r l u s t ~hut,, on the other l~nnd,mnny of thcm will prolmldy have orcnsion UMIEROEADUATE LECTURE XNSl'RUCTION to u w or rvalunte the npplicntions of nurlenr chemistry. The usunl t w m m e s t e r lecture course in elementary Nnny potcntinl users of t l ~ e wtechniques will 1w crrnted physical chemidry hns become l w and less cnpnhle. of simply by impnrting the most rudinlrntnry knorvlrrlge handling effectively the incrensing numher of topics as- to the greatest possihle numlwr of sturlrnts. Thc time signed to it. At h'otm Dnme we have adopted the ex- may soon rome \vhm the Geiger counter is RS common ns pedient of devoting n third semester to topirs which the electronic pH meter, nnrl rertninly mnny nsperts of might he called "modern physicnl chemistry." In ad- its use nre no mom involvml. dition t,o uol>jertssuch ns ntomic and molecular st,rucGrnrlunte instrurtion nnrl re.warch in nurlcnr chemture, this c o u m also inrludes approximately eight lec- istry continues to oprrntr a t n high level in mnny tures on nuclear physics and chemistry. Olwiously, schools, clrn\vinp on the fund of tnlrnt and knowledge this brief trentment can do no more than state t,he bare arcumrtlntrd on the cnrious ntomic energy projects. easentinls. The main topirs are the produetion andprop- Horvrvrr, there exists nn unfortrmute tendency to re erties of unst:rhle nucli~lcsand the applicntion of these gnnl the field a s highly specinlized nnd difiwlt in 1111 its phenomena to the study of chemical processes. We ' \Vr~~.~rua, 11. It., JR., IV. H. IIAM~LL, A N D R. 11. SCIIULXR, hope at lcnst to leave the student with some apprecin- J.Cmm. ISooc.. 26,210, 310, ffi7(101!1). tion of the significance nnd scope of the mrthocls, if not \Vu.w~ns,R. It., JR., \Ir. 11. II.~u11.~, AND R. 11. SCHULCR, with its details. ibid., 26.1in7 (l!W!l).
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aspects. This is intensified hy the confinement of the instruction to the graduate level. I t Reems to us that some effort must now he matlc to integrate elementary aspects nf this work into our undergrn(1unte programs. 'Illis will require not only the efforts of t11e trncl~ersof
JOURNAL OF CHEMICAL EDUCATION
nuclear wienre but also cooperation from their colleagues and the various university, governmental, and manufacturing agencies which aid and service the tcaching profession. The possible benefits of such a progrnm arc obvious and genrrnl.
