An outstanding high-school department of chemistry - American

equipment provided by Shortridge High School of Indianapolis. The head of this department, Frank B. Wade, is a man of long experience as a teacher and...
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Vor.. 5. No. 12 OUTSTANDING HIGA-SCHOOL DEPARTMENT OR CHEMISTRY

1571

AN OUTSTANDING HIGH-SCHOOL DEPARTMENT OF CHEMISTRY

With no thought whatever of suggesting invidious comparison but only in the hope of stimulating a deeper interest in the problem of giving our boys and girls a challenging introduction to chemistry, the readers of THIS JOURNAL are invited to consider the method of instruction and the physical equipment provided by Shortridge High School of Indianapolis. The head of this department, Frank B. Wade, is a man of long experience as a teacher and one who oossesses rare skill in exciting and cultivatine an interest in his subject. He is widely known not only as a teacher of unusual ability, but also as a chemist and as an expert on precious stones. He has represented the Indianapolis Section in the Council of the American Chemical Society, has been president of the Indiana Academy of Science, and has always taken an active part in the annual meetings of the science teachers of his state. He bas sent a large number of students to our colleges and universities; many of them are now occupying prominent positions in educational institutions and in chemical industry. A modest resent at ion of the ~ l a n FRANK B. WADE by which Professor Wade leads his students into the field of chemistry follows a brief description of the splendid new laboratory into which he has recently moved-a fitting reward for distinguished services of the past, an inspiration to greater efforts now and in the future. Equipment The new building of Shortridge affords the chemistry department more space than has been available in recent years. There are three laboratories, each accommodating a maximum of twenty-four pupils a t a time. This limit is built into the laboratories in several ways so as to make almost impossible the crowding of pupils into larger sections than those of twenty-four each. Thus a good deal of individual attention can

always be given to the pupils. There is a classroom with lecture table for demonstration work. In the rear of the room is a departmental library with separate doors for entrance and exit, to prevent disturbing classes in the room. Another classroom with small lecture table is also available. A large stockroom is built in between two of the laboratories and across the corridor from the lecture rooms. The day's program includes four double periods in chemistry. There are four hundred thirty-two individual drawers for apparatus in the three

laboratories; thus it is desirable that the department keep that number of pupils as a maximum. Alberene stone desk tops and bottle shelves have been specified. In addition to the four hundred thirty-two lock drawers there is a sufficient number of open drawers a t every desk so that apparatus to be used by every pupil on occasion are right a t hand. Waste-jars convenient to every pupil are provided beneath the desks. The sinks are of the square type and so located that the pupils will have least lost motion. Both d. c. and a. c. current are available for each pupil a t his own place. Sectional bookcases for notebooks are kept on special shelves near the door so that pupils may take their notebooks on entering the room and

leave them on going out. Key boards for each section are located near the doors. Balances are kept on shelves along the outer walls of the laboratories. Instruction The department conducts five double periods per week (eighty-five minutes per day) for thirty-eight weeks. This arransement was obtained for all the laboratory science courses of the school through the influence of Charles W. Eliot of Harvard University while on a visit to Indianapolis many years ago. He was at that time professor of chemistry a t Harvard.

The conscious purpose of the department is not to teach chemistry, but to try to train boys and girls to use their heads in connection with the study of some few of the fundamental facts and laws and theories of general inorganic chemistry. To this end the beginnings of all the topics, so far as possible, are made in the laboratory; classroom discussion and then write-up of the work follows. When a particular topic has been covered in this way, the textbook and the reference texts are consulted. This is done almost entirely in the department and under supervision. A large departmental library is kept available to all the pupils and they are taught to use it. Written

examination next follows, more as a teaching exercise than as a test. The questions are framed to compel the pupils to make use of what they should have learned, not to find out whether they have memorized the facts. This method is very slow and not much ground can be covered in a year. However, what is covered is learned thoroughly and there is not much duplication when pupils take beginning college chemistry. Those pupils do not have all the newness taken off their college work. The few fundamentals which they do learn in high school can very well stand the review of the college course and a t the same time the college professor will go more deeply into some of the topics. For those who do not go to college the discipline of the course as taught is invaluable and they get enough chemistry to have a very good idea of what i t has done, is doing, and may he expected to do for modern civilization. Most of the topics in the Standard Minimum Outline of the American Chemical Society Committee on Education are covered. The order of treatment of the work is original. At the outset the chemistry of "Earth, Air, Fire and Water" is studied, beginning with the action of air on hot metals; then in the rusting of iron the gain in weight of the oxidizing metal is noted by the pupils, and they reason out that something is taken from the air. The loss of volume of the confined air above the sting iron again gives them an argument that something is taken from the air in rusting. A candle is next used and its products on burning are caught, studied, and the weight taken to prove gain in weight during burning. The human body is next likened to the candle and its products seen to be similar (water and carbon dioxide), and the production of heat and an elevated temperature in both the case of the candle and that of the body is noted. Decaying leaf mould next is studied and the production of heat and carbon dioxide noted. Thus the oxidation of heated metals, the rusting of iron, the burning of fuels, and the combustion in the body and in decay are all related to the oxygen in the air. Oxygen itself is next studied as a natural sequence. Also carbon dioxide and monoxide and the properties and uses of these gases are of course considered. The air is then further explored and its oxygen removed. Here the gas laws and calculations to changed conditions must be taught. The residual nitrogen is then studied, followed by the rare gases. Water is next taken up and studied as a substance and as a solvent, and the laws of solution and the idea of equilibrium in solution are set forth. Then decomposition of water (as steam with hot iron, first) is brought about (active metals next) and the presence of hydrogen discovered. Quantitative composition by volume and by weight comes next and the dual character of the hydrogen of water is brought out by displacement with sodium, followed by displacement of the second portion of the hydrogen with hot zinc dust acting on the residual sodium hydroxide.

VOL. 5, No. 12 OUTSTANDING HIGA-SW~OOL DEPARTMENT OF CHEMISTRY

1575

As hydrogen was discovered by the pupils in water, it is next prepared in quantity and studied. Thus as natural a sequence as possible is used throughout rather than a systematic order. The pupil thus proceeds always from the known to the unknown. Much time is put on the development of the atomic theory from the facts of the laws of definite and multiple proportions, and sample cases of definite proportions are shown by comparison of accurate analyses made by the teachers for every beginning section, using the synthesis of magnesium oxide as an example. The weight composition of water as shown by many analyses and syntheses is another case of definite proportions that is used.

Hydrogen peroxide versus water, carbon dioxide versus the monoxide and other cases of multiple proportions are then cited. The atomic theory is then offered as an adequate explanation of these sets of facts. The GayLussac gas law is next set forth with the case of the volume composition of water as a basis. The volume composition of hydrogen chloride and of ammonia gas are given as additional material. It is shown that the atomic theory does not serve to explain the Gay-Lussac law. The Avogadro hypothesis is then offered and shown to be an adequate explanation of the gas laws, and use is then made of it to obtain molecular weights and for-

mulas. No use of formulas is made until the atomic theoryand the Avogadro hypothesis give adequate basis for them. Thus a real understanding of the significance and origin of formulas can be given to the better pupils. For many years the department has segregated one or more groups of the twenty-four better pupils after the first semester and put them through a more rigorous course in the second semester. It has been found to he good both for the brighter ones, who get harder competition, and for the weaker ones, who are not discouraged by the speed of the better pupils. In the last six weeks of the second semester these brighter pupils are given project work in committees of two to four pupils. The committees use the library and read up on their topics, then look up experimental work, perform it, visit factories or other plants as need may require, and report to the class on the complete result of their study. In the last two or three weeks some original research of a simple nature is often done by the better groups. A third semester of chemistry is offered each spring semester to a few pupils who have proved to be especially capable and who desire to get positions as assistants in commercial laboratories for a year or so to earn money to go to college. This Chemistry I11 course is one in the fundamentals of quantitative analysis. While no qualitative analysis has been done by these pupils, it is found that they can readily study the reactions employed in the quantitative work as they proceed, and the industrial men who employ these boys and girls are a unit in demanding this sort of work. The pupils learn to be neat and careful, to wash their glassware clean, to be strictly honest in their work, to use the analytical balance rapidly and accurately, and to comprehend standard solutions, the use of indicators, end-point, and so forth. Acidimetry and alkalietry are, of course taught and some oxidation-reduction reactions are studied. Iodimetry is also given. At present there is more demand for good students in local industrial laboratories than can be supplied.