Laboratory Experiments in General Chemistry

......... 28 V . Equivalent Weights. Formulas. Equations ............. . . . . 31 V1 . Review Exercises ................................... 38 V11 . The Halogens ...................................... 40 V1 I1 . Acids, Bases, Salts . Chemical Equilibrium ............ 47 IX . Ammonia and Nitric Acid ........................... 52 X . Hydrogen Sulphide, Sulphur Dioxide, Carbon Dioxide 55 XI . The Atmosphere, Flame . Oxidation and Reduction .. 63 XI1 . Ionization ......................................... 70 XI11 . Elective Qualitative and Quantitative Experiments ..... 72 XIV . Some Inorganic and Organic Preparations ............. 76 . . Appendix .......................................... 84 ...- PREFACE The experiments outlined in this manual are designed primarily for college students who have not had a course in chemistry in a preparatory school. The exercises represent the laboratory work of a comparatively brief introductory course in General Chemistry. The experiments are to be conducted under the guidance of an in- structor, and are to be supplemented by class-room demonstrations in connection with recitations from a text-book in General Chemistry for college students, or by illustrated lectures and text-book assign- ments. Frequently the experiments do not furnish sufficient information to enable the student to answer some of the questions and make the explanations that are to appear in his notebook. The necessary information can generally be obtained from the text-book, and it is my plan to have the student use the text-book and laboratory outline as cowanion volumes in the laboratory. To facilitate the stu- dents progress in this connection page references to two widely used texts have been inserted. My experience goes to show that the student will thus make very efficient use of his time, that he will give care and thought to his work, and that the laboratory work can be successfully made the central feature of instruction in the course. In preparing the experiments, the substances chosen for study have purposely been limited to avoid scattering the students efforts. Intensive, rather than extensive, study has been the underlying idea in slecting the exercises. Extended experiments on the metal- lic elements have not been included, as I feel that this work should be undertaken in Analytical Chemistry, and be allotted some of the time so largely used for laboratory practice in following a scheme of separations. I fully realize the value of practice in the identification of unknown substances, and this feature of laboratory work has been duly emphasized, and, it is hoped, in a manner which preserves its educational value. Emphasis has also been placed upon the gen- eral reactions of acids, bases, and salts, the processes of oxidation and reduction, and chemical changes prominent in everyday life. My experience has been that the work outlined is adequate in scope as Preface 5 a preparation for more advanced courses in chemistry, and that it offers the cultural benefits of laboratory work to the student who wishes to take only elementary chemistry as a part of his college course. The benefits of laboratory work, of course, lie more in the hands of the instructor than in the pages of the book, and fully as much in the enthusiasm and spirit of inquiry of the student as in text-book matter and qualities of the teacher... --This text refers to an alternate Paperback edition.