The content of final examinations in the first course in college

A look at the frequency of topics appearing on first year chemistry final examinations over several decades. Keywords (Audience):. First-Year Undergra...
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The Content of Final Examinations in the First Course in College Chemistry Robert H. Goldsmith St. Mary's College of Maryland. St. Mary's Clty. MD 20888 The extent of changeinthe course content of the first-year college chemistry course has been a topic of active interest over the last three decades. A formal scale for rating preselected topics was developed by Neckamkin ( I ) in 1961 and used to rate topics as to their desirability for a place in this course. Jones and Roswell (2) used a similar approach in 1973. Ryan and Kellams (3) in 1980 evaluated the importance of topics by considering the extent of inclusion of selection t o ~ i c sin textbooks and in the ACS standardized examinations. Jav Youne (4) in 1964 carried out the first study of the topi& that k i r k included in general chemistry examinations. He indicated that examination questions were a better

reflection of course content than subjective commentary by instructors concerning what should be included in a course as opposed to what the instructor actually covered. This initial study involved the collection and classification of 5,600 questions obtained from 52 sets of final examinations for the 1962-1963 academic year. This author ( 5 ) repeated this study using6146 questions obtainedfrom 45 sets of final examinations for the 1974-1975 academic year. This study was carried out a third time so that previous results could be compared with data from the 19861987 academic year. Final examinations used in the first-year college chemistry course for this year were requested from 225 institutions. A follow-up request was submitted to an

Frequency of Toplu Appaarlng on Flnt-Year Chornlstry Flnal Exarnlnatlons Topic

1962-1963e 1974-1975b 1986-1987f

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Half-reactions Nernst equat10n Other Klnetlcs Rate constant Actlvatlon energy EIectrdys18 and conductance Other' Descrlptlve chemlsw General lnorganlc Advanced lncrganlc Organlc Advanced organlc Analytloal chemlstry Qualltatlve (Inorg.) Qualltatlve (organlc) Quantltatlve Instrumental Giher toplcs Elementary chemlcal physlcs Nuclear chemlshy Surface chemlstry Blcchemlstry Practical chemlshy Hlstorlcal, phllosophlcal Envlrcnmental ohemlsby Medlclnal chemlshv Polymer chemistry

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Laws" lnlenslve prcpeltles Stolchlometty The mole, equivalent wts. MalhematIcaIproblems' Concentration, tltratlon Logarithms, other Other Applled ThermodVnamlcs Essential prlnclples~ General applloatlonk Gsses

Solutions'

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lnnltutlm~ stvdied numbered 52 schools mat submlned 5.800 qwrrtlonr. lnnltutlons studied numbered 45 schwis that submlned 8. 148 qusstlona. lnrtltutlma studled numbered 50 rchwlr mat aubmlnsd 5.070 questions. Veorcentaga of the total number of examlnatlon questlono by toplc. 'crystal rtruoture, amorphous solids, X-ray dinractlon. llsomrlsm, allolropy. magnetic propenles. QPBUII~ X E I Y S I O ~prlndple, abmlc radii, lanmanlde comractlon. DC~nstam proponlons, conservation of masalenergy. multlple propmlonr du LongPstlt.

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1962-1963a 1974-197Sb 1986-1967'

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Fundamema1Rlnclples Klnetlc molecular theory Period10 table Bonds Valence, oxldatlon number Structure, bulke Structure, molecular' Structure, atomlc s, p, d, f notatlon Emlsslon specm lon128110n potentials Other0

Homogeneousequlllbrlum Heterogeneous equlllbrlumm Phase rule Vapor pressure Bolllno odnt Freezkg polnt

Toplc

Journal of Chemical Education

1 WelgM-weight relationships, percent composition, balancing equations. JEmropy,tree energy, thermochsmisw. *Henry's law. RaouIt's law. Le Chatelier's principle. 'Anivln, coefficient, osmotlc presrurs. one phase eystem: gaseous, pure llquida and solutlono; enen of temprmure and pressure on such, bunera. panitlon ooetflclent, hydr~gen elactrade. oorroslon, rolubilln,, and temperature. oPhotoshwmisry.radlatbn chemiaw, siecuo6e processes, mechanisms.

additional 25 junior colleges in urder t o increase the representation of this group in the sample. Examinations from colleges that indicated their final examinations reflected an overly high emphasis on recently covered topics or colleges whose examinations reflected a bias toward more recent coveraee were removed from the studv. - Fiftv acceDtahle examinakons were used in this study. The topic list used in the initial study plus the additional four topics added in the second study was employed. Items were classified as specifically as possible under one of the specific topics or subtopics. Notes are used to help in the classification of certain ambiguities and are present following the tahle in order t o gi;e more accurate information concerning a given topic or subtopic. Information on the size of the school and its location was also collected. Seven schools were from the Far West, 10 were from the North-Central east of the Mississippi, seven were from the North-Central west of the Mississippi, 13were from the South. and 13 were from New Eneland and the eastern neighboring states. Geographically i h e sample is weighted toward the eastern and southern parts of the country. The 50 schools were also classified accordine to size as follows: community colleges (32%), small colle& and universities containine UD t o 3.000 students (34%). and those colleges and univ&kes with more than 3,000 students (34%). Contrasted with the proportions of 39% for junior colleges, 33% for the small colleges, and 28% for the larger schools that were calculated from data in the World Almanac, a sampling error of about 10%can be estimated. However, there is no reason to suppose that the subject matter taught a t junior colleges is significantly different from that taught a t other schools. The table was prepared by dividing the number of test items in a eiven cateeorv bv the total number of test items classified f;r this stud; which amounted to 5,070 items. Values are expressed in percentages. The values calculated for the 19861987 study are presented with the values previously determined for the 1962-1963 and the 1974-1975 studies. Available data allowed calculation of statistical differences between the 1974-1975 and the 1 9 8 6 1987 data. Statistical calculations including the "t" test were done in accordance with procedures described in Little's

book on experimental design (6).Detailed information from the 1962-1963 study was not available to this author, and therefore it was impossible to make any statistical comparisons with the 1962-1963 study. The data illustrate the relative usage of these topics for the three years of concern. We can say with over 9990 confidence that there has been a decrease in the attention devoted to the two topics, electrolysisand conductance, and mathematical problems. Several areas, such as emf, descriptive organic chemistry, and general applications of applied thermodynamics, that showed large percentage changes did not attain the desired confidence levels because uf their great variations in standard deviation. The data indicate that very little significant rhange has occurred within any of the cateOf the two topics that did show a sienificant decrease, rories. u i t can be speculated that a better student preparation including the growth of introductory chemistry courses emphasizing problem solving may have cut down on the need for as much coverage of basic mathematical problems, but this author must urge the reader t o speculate on the reasons for the decreased weight dven t o electrolysis and conductance. I t does appear that despite all the rhetoricgiven to the importance of increased emphasis on descriptive chemistry that covereage of descriptive chemistry may be on the decrease and a t best is remaining a t above the same level. Reasons for the inattention to descriptive chemistrv mieht ---include the instructor's belief in the beater relative importance of various nondescriotive t o ~ i c sand the difficultv of writing goodquestions in this area. I t implies that, if changes in coveraee are reallv wanted, then more work is aoine . .to have to bedone to rake the lev& of instructor's interest and the amount of time devoted to descriptive chemistry and other special topics. Each reader will have to consider the data carefully in light of that person's unique responsibilities and situation. ~~~

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Literature cned

Volume 68 Number 8 August 1991

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