VOLUME 33, NO. 5, MAY, 1956
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TEACHING COLLEGE CHEMISTRY TO SELECTED HIGH-SCHOOL SENIORS SAUL GEFFNER' Far Rockaway High School, Far Rockaway, New York
IT
IS the purpose of this paper t o report on the attempt of one secondary school to offer a course in college-level chemistry to selected high-school seniors. The author, a member of the chemistry committee of the School and College Study, has had some seven-years experience in teaching college chemistry courses. The course was offered a t the Far Rockaway High School in New York City during the academic year ending in June, 1955, and was a part of the program developed by the School and College Study. The publications of this committee express its philosophy and practice^.^ Suffice it t o say, a t this point, that one of the major considerations in offering such courses was to make students, especially gifted seniors, work up t o capacity during the last year in high school. The growing demands of applied science and technology have brought this problem sharply into focus.
' Present address: Chairman, Science Department, Forest Hilla High School, Foreat Hills, New York. School and College Study of Admission with Advanced Standing, Office of the Executive Director, Central High School, Philadelphia 41, Pennsylvania.
Far Rockaway High School is a general community high school, serving the needs of all types of students. From a group of 400 seniors, 11 students were selected for participation in this course, on the following bases: (1) General school average for three years (2) Intelligence quotient (3) Reading and arithmetic scores on standardized tests (4) Interest and zeal in subject
There were no prerequisites. We insisted that no student be allowed to take such a course if it involved his dropping physics. One pupil was forced to drop the course due t o prolonged illness. Of the total membership of ten pupils, six had had a previous course in highschool chemistry while four had no previous work. Reference t o the paper by Nortona will make clear that the chemistry subcommittee did not suggest an actual course of study to be followed. Instead they made reference t o many subject-matter areas where WORTON, BAPESM., J. CHBM.EDUC.,33,232 (1956).
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they felt the maturity and intellectual power of the student would be revealed to the best advantage. I n the course here being described, the following subject areas were studied in approximately the order listed: (1) General introduction-scientific method. (2) Properties of gases, liquids and solids. (3) Development of the modern atomic theory: this included an intensive study of the periodic classification. Also included were the coarse and fine structure of the atom. Subshell atomic structure was related to the element's ~ositionin the ~eriodictable oulv. (4) 1ntrod;ction to elementary nuclear chemistry. (5) The nature of the chemical bond. The properties of polar, polar covalent, covalent, and coordinate covalent linkages were studied. Emphasis on modern theories such as hydrogen bonding were included. (6) Chemical equilibrium-qualitative and quantitative aspects. (7) Solutions-applications of Raoult's law. (8) Theory of ionization-including strong and weak electrolytes. I n addition, the Bronsted concept was developed and applied t o acid-base reactions including hydrolysis. The concepts of hydrogen ion concentration and pH were included. (9) Equilibria in salt solutions including solubility product applications. (10) Electrochemistry-concepts of oxidation potential, oxidation-reduction reactions, electrolytic and voltaic cells. (11) Descriptive chemistry of the compounds of the alkali metals, halogens, sulfur and selenium, nitrogen and phosphorus, and chromium and manganese. (12) Qualitative analysis-silver and copper groups only.
JOURNAL OF CHEMICAL EDUCATION
(10) Reversible reactions and equilibrium (11) Equilibria involving volatile and insoluble substances (12) The titration of acids and bases (including:standardization) (13) Oxidizing and reducing agents (14) The preparation and properties of some oxyhalogen compounds (15) Principles of electrochemistry (16) The oxides of the elements and periodic table (17) Qualitative analysis-silver and copper groups
The class met from four t o five times a week for a 40minute period. I n addition, once a week there was a laboratory period of a t least three hours. The total of 17 experiments was performed during 25 laboratory periods. The method of teaching in class was largely of the lecture-recitation variety; demonstrations were infrequently used. No long-range scheduling of work to be done was utilized since it was difficult to predict the rate a t which the class could progress. However, to be sure to cover a t least the minimum essentials a general plan of work was adopted. This plan included the 11 subject matter areas mentioned previously and the approximate time to be spent on each area. There was however, considerable revision as the course progressed. During the first semester, units 1 through 5 were covered, 6 through 11 during the second semester. The students were given a t least three specific assignments each week exclusive of the lahoratory report. On the average, the total preparation per week per pupil ranged from four t o five houn. The teacher himself, although experienced in teaching college chemistry, also spent about the same number of hours per week on his own preparation. The school was fortunate in having six triple-beam Problems in the following areas were stressed: balances sensitive t o 0.01 gram and one analytical bal(1) Determination of atomic and molecular weights. ance sensitive to a t least 0.0001 gram. The precision of This included percentage composition, determination any experiment was limited to that of the triple-beam of a formula, application of gas laws, and weight and balance. Each student also was trained t o use the more volume problems. sensitive balance. Aside from these balances no special (2) Calculation of equilibrium and ionization con- equipment was necessary. For volumetric work, a 50stants, hydrogen ion concentration, common ion effect, ml. buret graduated in 0.1 ml. was used. Each pupil and pH of solutions. was given a kit of standard equipment a t the beginning (3) Applications of solubility product to situations of the school year. This kit comprised the usual glassencountered in qualitative analysis. ware, ironware, rubber stoppers, etc. The organization of the school permitted the students t o spend Friday The laboratory experiments covered were: afternoons for scheduled laboratory work. Occasionally make-up work was permitted during a Wednesday (1) Introductory laboratory techniques ( 2 ) Physical and chemical properties of substances afternoon. The textbook used in the course was that by Sisler, (3) The quantitative determination of oxygen in the VanderWerf, and Davidson.4 The text, although atmosphere (4) The determination of the formula of cuprous superb in organization, thorough and complete in treatment, is somewhat too difficult for any but the best sulfide (5) The equivalent weight of magnesium from the students. Pauling's "General Chemistry"' was used volume of hydrogen displaced 'SISLER,H. H., C. A. VANDERWERP, AND A. W. DAYIDSON, (6) The molal volume of a gas "General Chemistry: A Systematic Approach," The Maemillan (7) The molecular weight of a gas Co., New York, 1949. (8) The equivalent weight of a metal 'PAULING,LINUS,"General Chemistry," 2nd ed., W. H. Free(9) The concentration of solutions man & Co., San Francisco, 1953.
VOLUME 33, NO. 5, MAY, 1956
as a reference. Here again the students encountered obviously must he well trained in the field. The number difficulties, particularly with the subject of chemical of graduate degrees is in itself no complete indication of bonding. It appears that the new text by Steiner and his ability to teach this course. He must be a wellCampbell6may suit the needs of more students in future organized, patient, and persevering individual. He courses like this. For laboratory work, the manual by must he the kind of individual who will get much satisMalm and FrantzT proved t o he excellently adaptable. faction from a job well done. He must he willing to put The experiments are numerous, clearly written, and in additional time, much beyond what will he allotted beautifully illustrated. The introduction to each experi- to him. There must he a t least 10 teaching periods ment provides a fine summary of the theory needed to assigned to the conrse. This means that if a teacher perform these experiments intelligently. An additional normally teaches 25 periods each week, he will carry, in aid and a very helpful one is "Basic General Chemistry addition to this course, no more than 15 periods of work. in Outline F ~ r m . ' : ~This contains, in hound form, a set If he is chairman of the department, and normally carof lecture notes, questions, and problems. The experi- ries a smaller teaching load, he can use some of his enced as well as the inexperienced teacher will profit supervisory time to meet the time demands this course from this outline. will make. Students who have completed a year of high-school To assist in properly evaluating this course a questionnaire was drawn up and submitted to each member physics will experience less difficultyin the course than of the class. An analysis of the responses can be sum- those who have not. marized as follows: The college level course should be preceded by a highThe students as a group did not work hard enough. school chemistry course. Early planning in the stuThis may be due to some apprehension on the part of dent's career will allow his program t o he so adjusted the instmctor as t o how far he could go in view of the that he can successfully pursue this course. The normal fact that the students were carrying a full schedule. year's course in high-school chemistry can he comThere was also some conflict between this course and pressed to a one-semester course to be followed by two other senior commitments, especially during the after- semesters of college chemistry. There must be a minimum of five periods each week noons when the laboratory period was held. All the students found the laboratory period to he for recitation, discussion (lecture), and a complete afterfruitful although the group without previous training noon set aside for laboratory work. was at a loss a t the beginning. The lahoratory experiThe success of such a course will not he determined ments including the simplest ones assume some prior by the quantity of information the instructor can imknowledge. Despite attempts t o cover the theory in part. Instead, the curiosity he can arouse and the advance of the laboratory work, it was not always pos- imagination and thinking which he can awaken and sible to do this. The experiments related to pure de- stimulate will serve as more valid criteria for final scriptive chemistry were not as popular as those involv- evaluation. I n the lahoratory, the student must heing some degree of measurement. The two weeks spent come facile with equipment, to be sure. However, on qualitative analysis were met with much enthusiasm, understanding and appreciating the role of experimenpartially due to the student's greater laboratory experi- tation is a more far-reaching and more lasting goal. Needless to say, there are many proved methods for ence at this point and mostly to the inherent interest meeting the needs of the bright and gifted student. that analytical chemistry evokes. The topics the students found most difficult were: This paper has attempted merely to discuss one kind of (1) quantitative aspects of equilibrium, (2) electrochem- approach. The need for training scientific personnel istry, (3) Raoult's law. will become more acute in the years to come. SecondThe writer's experience prompts him to make the ary schools working together with colleges must confollowing suggestions to teachers who may he interested tinue to recognize this problem and develop programs t o meet these needs. in offering a course of this type. The selection of the instructor is one of the critical The writer wishes to express his appreciation to Prodeterminants of the success or failure of the course. He fessor Edward L. Haenisch of Wahash College for his suggestions and criticism in the preparation of this 0 STEINER, L. E., AND J. A. CAMPBELL, "General Chemistry," paper. The Maemillan Co., New York, 1955. He also expresses his appreciation to Professor Bayes ' MALM,L. E., AND H. W. FRANTZ, "College Chemistry in the M. Norton, Kenyon College, who, as chairman of the Laboboratmy," W. H. Freeman & Co., San Francisco, 1950. chemistry committee of the School and College Study, E. L., AND Qum, G. N., "Basic General ChemisHAENISCH, try in Outline Form," 5th ed., Burgess Publishing Co., Minne- provided him with the spark and ambition to do the job described in this report. apolis, 1953.
