JOURNAL OF CHEMICAL EDUCATION
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best seller book, ''Why Johnny Can't Read," when he assebts that the reason why is merely that no one ever taught him to read by the sound methods of phonetics. Diligently I have sought a n answer to the question why we have so many failures in our freshmen classes of chemistry for pre-engineers, pre-medics, pre-dental students, chemistry majors, etc. It does not seem t o be mathematics background. It certainly is not a matter of having had high-school chemistry or not. It seems to be that an important factor is lack of comprehensive reading ability. They call off words, but do not get the thought or the idea expressed by the words. Their knowledge of sentence structure is poor, their vocabulary is weak. They just do not know what the sentence states. Why? The question was asked by 0. M. Smith and C. E. Marshall (THISJOURNAL, 31, 658 (1954)): "What are the factors responsible for the drop in bachelor'sdegree chemistry graduates?" It is just as important to ask: why do so many freshmen in professional chemistry courses fail? The Chemical a d Engineering News reports (33, 4632 (1955)) more chemistry graduates in 1956 are expected than in 1955. Even though this be true, the questions, cited above, remain to be answered. I n his recently published book, "Restoration of Learning," Arthur Bestor points out that many of our schools emphasize "life adjustment" a t the expense of the basic three R's of learning. He presents a positive program of reform, which should increase the ability to recruit more future chemists and engineers. Teaching college freshmen begins in the first grade.
T o the Editor: I n many laboratory manuals the method for demonstrating the percentage composition of air calls for a graduated cylinder or eudiometer with iron filings adhering to its inner surface t o be immersed month down in a battery jar of water. A piece of yellow phosphorus in a coil af copper thrust into the trapped air may substitute for the iron filings. A day's wait is necessary before final results can be determined for the percentage of oxveen removed from the air. This time is reauired " for the iron to rust or the phosphorus t o form phosphorns pentoxide or phosphoric acid. There are many objections to this splitting up of the experiment. I suggest the following variation. Place two small peesized pieces of clean white phosphorus in a large Pyrex test tube, one a t the base of the tube, and the other about half way up. Stopper the tube by holding a rubber stopper lightly but snugly in place in the mouth of the tube. Holding the tube horizontally, heat it gently but sufficiently to cause the J. S. HICKS pieces of phosphorus to catch fire. After burning S m HOUSTON STATET E A C ~ E R COLLEQE S ceases, cool the tube under the tap, insert the mouth HUNTSVILLE, TEXAS into the battery jar of water, and then remove the stopper. proceed as in the standard method, determining the volume of water in the tube as well as the volume of the entire tube minus the space occupied by T o the Editor: the stopper. Calculate the percentage of oxygen in the An interesting variation of the procedure for the air. standardization of oxalic acid by potassium permanI have obtained uniformly excellent results by this ganate is to carry out the titrations in the cold with method easily within a 10-minute interval. One impor- decinormal solutions, using catalysts. tant word of caution: Care must be taken to burn out imTo 25 ml. of the oxalic acid, 20 m!. of a catalyst f mediately any unozidized phosphorus. Otherwise, pain- acid mixture (0.5 g. of MnSOa .7H,O 10 g. of ZnSOd. ful burns may be caused to unwarned personnel. 7H20 100 ml. of 4.0 N HzS04)are added. When the permanganate is run into this solution with constant shaking, the decolorieatioo proceeds fairly fast a t room temperature (30°C. in this writer's laboratory) after a short initial lag. A lasting pink color is obtained a t the same end point as obtained by the conventional method T o the Editor: of hot titrations. Only a trace of the manganese salt My experience corroborates R. T. Sanderson's com- need be initially present as more is formed in the course ments in his letter (THISJOURNAL, 32,338 (1955)) that of the reaction. A large amount is undesirable because greater ability in mathematics, reading, and writing it reacts with the permanganate to precipitate manwould better -prepare a high-school student for college ganese dioxide. Cadmium sulfate can be used in place of the zinc salt. chemistry. It is possible that it is too late in high school to preARCOTVISWANATHAN Dare future scientists. Their training beeins manv LOYOLA COLLEGE M A D R AINDIA ~, years earlier. Perhaps Rudolf ~lesch-is right in hi"s
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