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HIGH-SCHOOL NOTES
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THE CHEMISTRY. EXAMINATION OF THE COLLEGE ENTRANCE EXAMINATION BOARD
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N 1937 the College Entrance Examination Board appointed a Commission to revise the requirements for the one-unit examinations in physics and chemistry. The membership of the Commission, which submitted its report a t the April, 1940, meeting of the Board, follows: Dean John T. Tate, University of Minnesota (Chairman) Doctor Otis E. Alley, High School, Winchester, Mass. Mr. Raymond B. Brownlee, Stuyvesant High School, New York City Dean Janet H. Clark, University of Rochester Mr. John C. Hogg, Phillips Exeter Academy, Exeter, N A-. H -..
Professor Erwin B. Kelsey, Yale University Mr. Alfred R. Lincoln, Technical High school, Springfield, Mass. Professor Duane E. Roller, Hunter College Professor Francis W. Sears, Massachusetts Institute of Technology Professor Mary L. Sherrill, Mount Holyoke College Mr. Howard A. Taber. Hotchkiss School. Lakeville. Conn. The report consists of proposed syllabi in physics and chemistry. The chemiitry- syllabus is below in the belief that it will be of interest to all teachers of chemistry. This syllabus, together with the physics syllabus, will be presented to the B o d for action in October. In the meantime the Executive Secretary of the Board will welcome suggestions and criticisms from those interested. Communications should be addressed to the office of the College Entrance Examination Board, 431 West 117th Street, New York City.
will be more effectively taught if the instructor is given greater latitude in the selection of topics. The syllabus is divided into two sections: (1) a minimum syllabus, Part I and Part 11; (2) ~, an extension svllabus. Part 111, which is subdivided int; (a) commercial chemistry, (b) theoretical chemistry, and (c) organic chemistry. Candidates will be examined on the minimum syllabus only. Quantitative problems may be set upon those topics marked with an asterisk (*). In order that the objectives of the course of study may be fully realized, it is essential that the study of chemistry be accompanied by individual laboratory work as well as by class demonstrations. The laboratory work should occupy approximately one-thud of the time devoted to chemistry and it should continue throughout the whole course. A list of experiments is not submitted as i t is believed that the experiments will need to be varied according to the facilities of a particular institution. The arrangement of the syllabus does not imply a teaching sequence. PART I.
GENERAL CHEMISTRY
1. Chemical Changes. A. Element, compound, mixture. 1. Chemical change versus physical change. 2. Significance of t e r m s a t o m , molecule, radical. 3. Types of chemical reactions. 4. Electrochemical serieslimited to disTHE CHEMISTRY S n L A B U S placement reactions. B. Balancing of simple equations. The following suggested redefinition of the require*C. Quantitative relationship in chemical reacment in chemistry indicates the nature and extent of tions. the basic preparation considered necessary for college 1. Significance of symbol, formula, equawork. It is estimated that from two-thuds to fourtion. fifths of the school year will be required to cover the 2. Laws of combining proportion. basic topics suggested in the minimum syllabus given 3. Percentage composition. by Part I and Part 11. Part I11 is intended to show 4. Problems based on chemical equations: how the basic material of Parts I and I1 can be ampli(a) weight relationships, fied. Additional specific material designed to meet the (b) volume relationships. needs of the community and adapted to the level of the 5. Neutralization (quantitative). student body should also serve to enrich the basic Normal solutions. course. Questions on topics beyond this suggested area will not be included since i t is felt that the science 11. Physical Properties of Solids, Liquids, and Gases. 443
A. Kinetic molecular theory-relation between temperature and speed of molecules. Dierences between solids, liquids, and gases from kinetic molecular viewpoint. *B. Gases: 1. Effect of changes of temperature and pressure on the volume of gases. Explanation in terms of the kinetic theory. 2. Partial pressures of gases in a mixturerelated only to vapor pressure of water. 3. Reduction to standard conditions (including vapor pressure of water). 4. Avogadro's Law: derivation of gram molecular volume from a knowledge of the density and molecular weight of a gas. 111. Periodic Law. Brief treatment giving variation in properties of the elements as one proceeds horizontally and vertically through periods and families. Anomalies. IV. Structure of Atoms. A. Units of structure. Proton, neutron, electron, characterization as to mass and charge. . B. Atomic number. Nuclear charge and arrangement of electrons (hydrogen through calcium). Isotopes (hydrogen, chlorine). C. Explanation of periodicity in properties of elements in terms of atomic structure. D. Ionic valence and its relationship to inert gas structure (hydrogen through calcium). E. Chemical combination explained in terms of atomic stecture. 1. Electrovalence-combination and displacement; %eactions in terms of electron transfer (oxidationreduction). 2. Covalence-sharing of electrons in formation of un-ionized molecules. V. Electrolytes. A. Physical evidence of dissociation in fused salts and bases and in water solutions. B. Complete dissociation of salts and strong bases. C. Ionization of acids. 1. Ionization of acids by reaction with water. Distinction between a proton and the hydrated hydrogen ion (hydronium ion). 2. Degree of ionization of weak acidsionic equilibrium. D. Completion of ionic reactions by: 1. Formation of a slightly ionized product:
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2. Formation of an insoluble gas or solid. E. Hydrolysis of salts (reaction of ions with water). F. Electrolysis of water solutions.
In general, the study of any element should be developed in the following sequence: history, occurrence, preparation (most important laboratory and commercial methods), properties (physical and chemical), uses, and identification. Historical treatment should be limited to cases where i t offers a sound teaching approach and where it is of particular significance in the study of an element; for example, as an introduction to oxygen and hydrogen. Similarly, the study of the important compounds of the elements should include preparation, properties (physical and chemical), uses, and identification. As illustrative of a typical study of an element and its important compounds, the topic Nitrogen is given in expanded form a t the end of Part 11. I. Chemistry of Some Non-metals and Their Common Compounds. A. Oxygen. B. Hydrogen. C. Water. 1. Composition by weight and volume. 2. Purification. 3. Chemical reactions: (a) With oxides, basis of classification. of metals and nonmetals; (b) With salts to form hydrates. 4. Solutions: (a) Significance of term-saturated, unsaturated, molar. (b) InterprPtation of solubility curves. D. Carbon (allotropes). 1. Carbon dioxide and carbonic acid; types of carbonates; test for a carbonate. 2. Carbon mpnoxide. E. Halogen family. 1. Chlorine; hydrogen chloride and hydrochloric acid; hypochlorous acid. 2. Bromine, iodine, fluorine, and the hydrogen compounds, as compared with chlorine and hydrogen chloride. 3. Tests for chloride, bromide, and iodide ions. F. Sulfur. 1. Hydrogen sulfide, sulfides. 2. Sulfur dioxide-sulfurous acid, sulfites, bisulfites. 3. Sulfur trioxidesulfuric acid, sulfates, bisulfates.
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4. Tests for sulfide, sulfite, and sulfate ions. G. The atmosphere. 1. Air as a mixture. 2. Nitrogen and the rare gases. H. Nitrogen compounds. 1. Ammonia-test for ammonium ion. oxide and 2. Oxides of nitrog-nitric nitrogen dioxide. 3. Nitric acid. Test for nitrate ion.
11. Chemistry of a Typical Metal. A. Sodium and its compounds. 1. Sodium hydroxide. 2. Sodium chloride. 3. Sodium carbonate and sodium bicarbonate. 4. Sodium nitrate.
(2) Commercial: oxidation of ammonia (Ostwald). (b) Properties. (1) Physical. (2) Chemical. (a) Reaction of concentrated and dilute acid on (i) metals, (ii) non-metals, (iii) salts. (6) Test for nitrate ion. G. Nitrogen Cycle. PART 111.
EXTENSIONS
Parts I and I1 give the basic material for preparation for college work. It is recommended that the basic material be supplemented by topics from Part III and also by various items of current and local interest. 111. Nitrogen (Outlined in Expanded Form for IllusI. Commercial Chemistry. trative Purposes). A. Chemistry of four metals and their common A. History. compounds: aluminum, iron, zinc, and B. Occurrence. copper. C. Preparation. 1. Occurrence and extraction of these four 1. Atmospheric nitrogen. elements from their ores. 2. Pure nitrogen. 2. Simple reactions of these elements and D. Properties. identification of their ions. 1. Physical. B. Fuels. 2. Chemical. 1. Coal gas, producer gas, water gas. E. Uses. 2. Acetylene. F. Compounds. 3. Petroleum and natural gas; distilla1. Ammonia. . tion and cracking process. (a) Laboratory preparation. 11. Theoretical Chemistry. (b) Commercial preparation. (1) Synthetic (Haber). A. 1. Oxidation-reduction by electron transfer, as illustrated in the reactions of (2) Cyanamid. (c) Ammonium compounds. Part 11. (d) Test for ammonium ion. 2. Ozone, hydrogen psr~xide,other per: oxides, atomic hydrogen. 2. Oxides of nitrogen. c *B. Determination of: (a) Nitric oxide. 1. Equivalent weight. (1) Preparation by: 2. Molecular weight. .. (a) oxidation of am3. Application of these to the detetmonia (Ostmiuation of atomic weights. wald) , C. Equilibrium, mass action law and principle (b) reduction of niof Le Chatelier as applied to: tric acid. 1. Synthetic ammonia (Haber process), (2) Identification. 2. Contact process for preparation of (b) Nitrogen dioxide. sulfuric acid, (1) Preparation by: 3. Common ion effect with weak elec~ (a) oxidation of nitrolyte. tric oxide, (b) reduction of ni- 111. Organic Chemistry. tric acid, A. Simple organic reactions. (c) heating of niB. Foods. trates. 1. Components: carbohydrates, fats: proteins, vitamins. (2) Identification. 2. Hydrolysis. Uses of starch and 3. Nitric acid. sugar. (a) Preparation. 3. Fermentation. (1) Laboratory. :
