Rod O'Connor The Municipal University Omaha, Nebraska
Chemistry for Parents and Children An experiment in community service
For several years the College of ~ d u l t Course Outline Education a t this university has experimented with First Week Lectuw: "Inside the Atom" Discussion: protons, electrons, neutrons, isotopes, ions, courses for the parent and child. In the spring of 1957, nuclear transformations, radiation detection, chain reactions, Dr. D. N. Marquardt of the chemistry department, in cooperation with Michael Beilis of the College of Adult Education, originated a new course called "Exploring the Sciences for Parents and Children." Included were two Saturday mornings each of demonstrations and lectures in chemistry, physics, and biping-pong balls and mousetraps, mushroom cloud from black ology. Response to the program wasuniversally favorpowder. able, with each six-week program averaging an attendLaboratory: "Radiation Detection" A cloud chamber was demonstrated, the students were allowed ance of thirty adults and children. Repeated reto examine and use a. Geiger counter, and each student conquests for a longer study of chemistry led to the destructed, fallowing instructor's demonstration, an electr* velopment of the new course, "Chemistry for Parents scope from a small gat-collecting bottle, a rubber stopper, and Children," with six Saturday morning sessions some thick copper wire, and some thin metal foil. for parents with children 10 to 14 years of age. Second Week Lecture: "The Chemistry of the Atom" Discussion: valence electrons, elements, compounds, chemiThe very favorable results of this program led to the cal change, bonding, some simple reactions, energy from desire to share some of the ideas and details involved chemical change. with others who might wish to use such a plan. Typical Demonstrations: decomposition of ammonium diThe program was set up with a tuition charge of chromate, sodium plus u-abcr containing phenolphthalein, bssium hydroxide plus exhaled carbon dioxide followed by six dollars per person for the six-week period. Thus regeneration of the carbon dioxide with acid and its rea maximum allowed enrollment of thirty persons would c~mbinstionwith barium hydroxide, "Old Nassau" reaction, pay the salary of the instructor and a student assistant, cold flame, "whistling hydrogen bomb" explosion. as well as provide some payment for chemicals and L a b o d m y : "Prepasation of Oxygen and Milk of Magnesia" equipment needed. Remaining costs were contributed Each student was provided with safety goggles, a large test tube, stopper, tubing and hose, burner, water trough, and by the University. Each session was divided into one gas-oallecting bottles. Following stepwise the instructor's hour of lecture and demonstration followed by one hour demonstration, each student assembled an oxygen generator of laboratorv work which eave each ~ a r t i c i ~ a n t a ~ r o d ~ ~ tand added some potassium chlorate-manganese dioxide of his own "making thatuhe could' keep.' All iectures mixture. Before heating x a s begun, each set-up was cheeked by the instructor or his assistant to be sore no were on a descriptive, nonmathematical basis with the chemicals were in contact u-ith rubber and that everything demonstrations designed as teaching aids, rather than was workable. Then the tubes were cautiously heated and as simple entertainment. Verbal quizzes from time two bottles of oxygen %ere collected. The students were to time showed that both parents and children did shown haw to test with a glowing splint for the "purity" retain a large amount of material. The laboratories of their oxygen. Finally a, one inch strip of magnesium was held in tongs, ignited, and dropped into one pyrex flask were conducted on a demonstration-follow basis with of oxygen. Two ml of m t e r were then added and the susthe instructor standing on a table performing each step pension of magnesium oxide poured into small vials so that of the experiment and the students then following in the students could take home their "milk of magnesia." "lock-step" fashion under close supervision. This Third Week Lecture: "Acids, Bases, and Salts and Silicon allowed several experiments to be performed which Chemistry" Discussion: the molecular structure and behavior of some would have been difficult or impossible for parts of the common acids, bases, and salts, some chemistry of silicon. group by "cook-book" type procedure. Whenever Typical Demonstrations: tastes of acids, bases, and salts; hazardous chemicals were involved, such as concenvapor phase neutralization of HC1 and NH8; colored inditrated sulfuric acid, the reagent was added to the cator reactions; molecular models and examples of asbestos, mica, quart^; ion exchange separation of cupric dichromate. individual's mixture by the student assistant or the Laboratmy: "Preparation of Hydrogen Chloride and Tablc instructor. An outline of the course follows and deSalt" tails of each laboratory are given. Most demonstraHydrogen chloride gas was prepared from sadium chloride and tions were obtained from THIS JOURNAL and from sulfuric acid in a test-tube generator, with the laboratory assistant adding the sulfurio acid to each generator. The "Tested Demonstrat,ions in General Chemistry."' ALYEA,H. N. "Te~ted Demonstrations in General Chem, B., "Chem. Ed. Tested Demonstraistry," AND D m o ~ F. tions," Division of Chemical Education of the American Chemical Society, Easton, Penna. 1
hydrogen chloride was bubbled through distilled nater and the aqueous acid was tested ~ 6 t various h indicators. Next, 8 solution of sodium hydroxide was prepared, tested with indicators, and neutralized v i t h the aqueous hydrochloric acid to a. litmus end point. A slight excess of acid was Volume 37, Number 7 2, December 7 960
/
639
added, the solution was placed in a beaker covered with a watch glass supported on glass hooks, and the solution was evaporated to dryness. After the beaker hadcooled, thesalt was removed, tasted, and transferred to a small vial for the student to take home. Fowlh Week Lecture: "The World of the Carbon Atom" Discussion: the chemistry of carbon, the covalent bond, Bome common functional groups, simple organic reactions, soaps and detergents. Typical Demonstrations: explosion of a charcoaldusted hydrogen balloon containing a paper airplane listing some of the myriads of wmpounds containing carbon, hydrogen, and oxygen; models of wmpounds containing different functional groups and samples of these compounds for odor; formalin clock reaction; esterification reaotion; deoomposition (explosion) of lead picrate; wetting action of detergents. Laboratory: "Preparation of Soap" Following the instructor's step-wise demonstration, each student carefully stirred a boiling mixture of 10 ml of cottonseed oil and 15 ml of 20% sodium hydroxide solution in a 10&ml beaker. Safety goggles were needed as a. protection against an accidental spattering. As the last of the water was boiled off, heat was decreased to avoid charring and the mixture was h a l l y cooled to obtain a waxy solid. The soap was washed three times with 20-mlportions of saturated sodium chloride solution and the wash liquid c~rtrefullydecanted. The cake was pressed dry between filter papers, molded into shape, and wrapped in aluminum foil for the student to take home. Fifth Week Lectwe: "The Large Organic Molecules" Di~cussion: polymerization, types of polymers. Typical Demonstrations: preparation of a thiokol ball, phenol-formaldehyde plastic, plexiglas, glyptal resin, nylon rope trick.' Labolatoly: "Preparation of Bakelite and Nylon" Eaeh student received a test tube containing 5 g of phenol crystals and 1 g of hexamethylenetetramine. The mixture was heated gently with constant stirring until it became homogeneous, then strongly heated until gas bubbles a p peared. At this point, the flame was removed and the reaction was allowed to oontinue without external heating until gas evolution stopped. The mixture was poured into an aluminum fail mold and the Bakelite plastic removed after cooling. Each student received two 4 m l test tubes, one containing 1 ml of a 2% joolution of sebacoyl chloride in carbon tetrachloride and the other containing 1 ml of an 8% solution of hexamethylmediamine in water. The contents of the second tube were carefully added to the first. A thread was caught at the liquid interface with a small Kre loop, pulled out, and wound around a small test tube. The nylon thread (and the students hands) were carefully washed and the
MOROAN, P. W., 182 (1959).
640
/
AND
KWOLEK,S. L., J. CHEM.EDUC.,36,
Journol o f Chemical Education
oamr thread blotted drv on filter . to be taken home by tbc student. Sixth Week LectWe: "Some Chemicalrr of Importance to the Body" Discussion: anesthetics, carbohydrates, amino acids and proteins, simple vitamins and hormones, common medicinals. Typical Demonstrations: odors of anesthetics, anesthetic action on an insect, dehydration of sucrose with concentrated sulfuric acid to form a carbon "snake," osazone formation, Benedict's test, reaction of starch with iodine (iodine clock), simulated bee sting, preparation of methyl salicylate ("external aspirin"), models of compounds. Labmztmy: "Preparation of Aspirin" Each student was provided with a 150-ml Erlenmeyer flask wntaining 10 g of dry salicylic acid, a stoppered test tube containing 14 ml of acetic anhydride, a warm water bath (60°C), and a small suction filtration setup. Following stepwise the instructor's demonstration, the students added the acetic anhydride to the reaction flask, allowed the lahoratory assistant to add 5 drops of concentrated sulfuric acid, and swirled the flask in the warm water bath for about twenty minutes. The flask was then cooled, 100 ml of distilled water added with stirring, and the crystals of product collected on a. Buchner funnel. The solid was washed with three 10 ml portions of 40% aqueous acetic acid and dried on the funnel by allowing air to be sucked through the system. The dried product was brought to the laboratory assistant, who pressed it into tablets with a small pellet press. Eaeh student took home his own aspirin tablets.
The program of chemistry for parents and children provided a valuable supplement to the grade school and junior high science programs. The superior students were allowed the opportunity of performing advanced experiments under the careful supervision of trained chemists. The contact of parents with chemical procedures and lahoratory safeguards undoubtedly will contribute to more careful control over home laboratory work by the children. The interest of many non-participants was aroused through presentation of reports to the home schools by the students in the chemistry class. I n addition to adding to the technical knowledge of parents and children and introducing them to the thought patterns of scientific work, the sessions served to provide excellent publicity and public relations for the chemistry department and the university. It is believed that a course such as this can do much in gaining and maintaining an interest in chemistry on the part of the young teenagers of the community.
