990
JOURNAL O F
CHEMICAL EDUCATION
AUGUST,1928
THE FIRST-YEAR COLLEGE COURSE IN CHEMISTRY FOR STUDENTS WHO HAVE STUDIED THE SUBJECT BEFORE ENTRANCE C. PAULINE BURT.SMITHCOLLBOB, NORTHAMPTON, MASSACHUSEIYS Any teacher called upon to organize a course in first-year college chemistry for students who have had an elementary course before entrance has a difficultproblem to face. Different colleges have solved the problem different ways. Some prefer to give full credit to the elementary course and so their students proceed into a second-year college course, which is usually qualitative and quantitative analysis. Others do not consider precollege courses worthy of merit and require such students to repeat their chemistry in the first-year elementary college course. A third type college has organized a special burse for these students. It is with this latter course that this article is concerned. This course must necessarily serve many purposes. I t may he needed to satisfy a science requirement or it may be used as a basis for a major in the subject. Then, too, i t must be sufficiently advanced for student$ who have had an excellent fundamental course, have passed the College Board entrance examination with merit and who naturally object to spending a year in review of the same material. In addition, the course must serve for those who are poorly prepared but choose to elect it. Diverse as these purposes appear to be, it is possible to satisfy all of them to a great degree in one course. An analysis of th% aims of a science requirement in an arts college seems to indicate that the study of a science should give a student power and training in observation, deduction, and correlation of scientific phenomena. Thus, facts are simply the necessary tools. It therefore seems that any exact science should serve the purpose and it follows that in an elementary chemistry course, the emphasis should not be-on the facts but on training in the use of those facts as was stated above. For those who wish to major in the subject, it is essential that they develop their abilities to handle the facts. Elementary courses giving an overdose of material to he memorized defeat their own purposes for their students majoring in the subject. Regardless of whether students are poorly prepared or not, granting that they have sufficient ability to enter Class A colleges, no course which demands less than the one satisfying a science requirement should he permitted them. The course described hereafter was organized with these ideas in mind and has been given here for the past two years with satisfactory results.
The Minimum Essentials Each student should know a t least the fundamental laws and theories of chemistry. Such understanding must come from much first-hand
observation and practice such as may be had in laboratory work. For that reason the amount of time spent in the laboratory should be great in comparison with classroom work-at least two or three hours per one of classroom work. Too many facts are usually crowded into an elementary course. If the emphasis is on their use as it should be, the number of facts should be minimized and above all they should be presented in proper relation to the theory. In such a brief article, i t is difficult to indicate exactly what theories and what reactions should be studied. Even in indicating the subjects, each person will interpret the volume of material as he sees fit. The order of the topics is almost as important as the topic itself. T h e e or four weeks spent in theoretical consideration before reaction chemistry is studied to any extent discourages the system of wholesale memorizing so prevalent among students. For the first semester's work, the following topics can be highly recommended. It is the outline given in Schlesinger's text on general chemistry and can best be gotten from that text. 1. Review of some fundamental concepts and definitions 2. Kinetic molecular hypothesis 3. Atomic theory, molecular and atomic weights 4. Symbols, formulas, and equations 5. Oxygen, hydrogen and water 6. Solutwns 7. ~ a l o ~ e n and ; the halides 8. Chemical equilibrium.
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The second semester topics have been given in the following order: 1. Complete study of ionization, equilibrium constants, etc. 2. Sulfur and nitrogen and their compounds 3. Precipitation, relative solubility, and solubility product 4. Periodic classification 5. Study of metals in groups. Thelast topic mentioned takes up a considerable portion of the laboratory, lecture, and class-discussion time of the second semester.' In other words, the material covered is a study of the reactions of the various metallic ions. It shonld not be called qualitative analysis, however, as the practice in analysis is truly incidental. The emphasis is on the study of principles governing these reactions. The reactions given in the first 65 pages of that inimitable laboratory manual on Qualitative Chemical Analysis by Stieglitz are carried out and studied.
The Laboratory Work In the first-semester laboratory assignments, an attempt is made to illustrate some fundamental laws, to review some reaction chemistry
992
JOURNAL oa CHEMICAL EDUCATION
AUGUST, 1928
in such a way that new relationships can be deduced and to put as many reactions as possible on a quantitative basis. Eight or ten quantitative experiments of the usual elementary type are carried out. There is a balance for every two students and, in weighing, an accuracy within a t least one per cent is required. A few gases are prepared in large quantity and all apparatus is subjected to strict observation and aiticism so that students are required to develop a respect for good technic in these as well as in the quantitative experiments.
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The Laboratory Notebook By far the most important part of the laboratory work is the organization of the notes which are recorded on a ruled form sheet under the headings of operations, observation, and special conclusions. All records must be brief and in the order of observation. The special conclusions must include the deductions from these observations and are recorded in the following order: substances used, conditions used, reactivity, products obtained, equation, type of reaction, and method of collection of produc:, if any. Questions and problems bearing on the use of this reaction are then answered on the same page. A general conclusion to the whole experiment is also demanded. This usually means the correlation of material from a number of special conclusions. This type of record lends itself easily to almost any type of reaction and a continued use of this method does much to develop logical thinking in a student. Experience has shown' that students find i t +n irksome method a t first, but later, gaining power in deduction and correlation, like it very much. This same method of note-taking is used during the second semester. The reactions of the metals are studied but, as was stated before, comparatively little time is put on analysis of groups. This does not seem to be a drawback even for a student who is taking a major in chemistry,'for in the study of the reactions, much of the technic has been used many times, the necessary facts are a t hand and a power for their use has been developed. A course in qualitative analysis which confines itself to separations is a great error for a first-year course. This is true for any college, university, or technical school, whether it furnishes a foundation for a major, for industrial work or serves as a science requirement in a college giving an arts degree. Classroom Work The lecture system is preferable to the much lauded textbook discussion system. Granting a good lecturer, much more can be done to train a student mind in well-presented material than in numerous hours of perusal of textbook pages, followed by discussion organized or unorganized. It is a question of the personality of the lecturer and of emphasis. Textbooks are notably lacking in style and necessarily lacking in personality.
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VOL. 5, NO.8
Fmsr-YEARCOLLEZECounsz IN CHEMISTRY
993
A judicious combination of the use of the textbook and the lecture gives excellent results. The following plan has been in use here for several years and can be highly recommended. At the beginning of the course, typewritten sheets (the size of the student notebook) are passed out. These sheets give the assignments for the whole semester, including text assignments, problems, and chapters to be covered by lectures. Before the lecture is given the assigned chapter must be studied and problems on that chapter handed in. At the beginning of the hour on that day, and as a check on the underwriting of the work already done on that chapter, a ten-minute written quiz is given. An attempt is made to ask questions which make thoughtful use of the facts. The lecture on this chapter then follows, important points are emphasized and obscure points cleared up. The ten-minute writtens are graded and returned. This method is a most satisfactory work-producing one. Students are eager to show their prowess, &ill, and innate abilities, and as a result gain power rapidly. Then too, knowing the material, they enjoy the lecture. A student is required to record lecture notes no matter how familiv the material. In spite of the excellent arrangement of many texts, the emphasis is not apparent to the beginning student. Therefore, the lecturer who indicates his outline and requires the recording of notes under a few important headings is showing arrangement and emphasis. The method in use has been to put the outline on the board before the class assembles and require th: students to take notes under the outline. Usually this plan followed systematically for a semester is unnecessary later as the student learns to do it for himself. A class discussion follows every two lectures. Such a discussion not only includes the material of these two lectures and the laboratory work for that week but any material which has previously been covered. This is an attempt to stop the memorizing of isolated facts and to place the emphasis on correlation. Hour written lessons are given four times per semester, and are a great aid to the students in that each requires a complete survey of the field to date. The final examination is the last gesture and i t rarely brings surprising results. Students who did not acquire power and understanding as the course progressed cannot do i t in several hours of concentrated cramming.
