WINNERS IN SECOND ''WEAT IS WRONG?" CONTEST In selecting the winners of the second contest' we have adhered to the iarne principles which guided us in the first and which may be quoted in xief as follows: "We have given most credit to observations relating to the chemistry nvolved and to correct laboratory technic. We have allowed some ?redit for criticisms directed a t minor or unintentional mistakes or omisions of the artist, provided they were based upon actual scientific observa:ion of laboratory conditions.. . . Criti6sms of the draftsman's technic which lid not involve scientific points were ignored as irrelevant. Erroneous itatements were penalized.. . .Other things being equal, more credit was
dlowed for a correction which included a statement of the reasons therefor than for a bare assertion." The winner of the five-dollar award was Alphonse Piekarski of Kirkwood, Missouri. His criticisms and drawing are reproduced herewith. I n order to facilitate in following along with the enumeration of the errors in the drawing, I have divided the errors under four main groups: errors that pertain to wrong 3rawing; those that are connected with necessary and unnecessary articles: and, finally, a miscellaneousgroup. The first division, dealing with wrong drawings, has reference to six objects. The I
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first object is the ringstand. The perspective of it is wrong, and furthermore, it could have been drawn much straighter. The second object is the basin. I n t h e drawing it is entirely too small. It should be large enough to contain a good amount of water (&O) in which the round bottom flask is placed. The third error in regard to wrong drawing is the thistle tuhe. The tube should be immened into the hydmehloric acid (HCI) and manganese dioxide (MnOn). The fourth error is that, according to the drawing, all tbe connecting glass tubes are clogged. I n this case, all the chlorine gas (CIS)would remain in the flask and in time break it, since the flask would he too small to contain the gas liberated by the hydrochloric acid. The fifth error is t h a t the mixture in the flask was not thoronghlv - .mixed. because if it were the &r of the mixture would be black. the manganese dioxide, the black powder, making it black. The sixth error is t h a t the hvdrochloric acid should be level and have no curves or mints as is shown in the drawing. The scconrl gmup dealing with unneccssxsy articles has three divisions. The antrnonium hydroxide SH,OH nnd thc canll,oard arc not ntcoanry. The ammonium hydroxide would only hinder the working of the experiment. Instead of having the ammonium hydroxide in the second wide-mouthed bottle, I put into i t the wet, colored cotton cloth, thereby leaving the dry colored one in the first widemouth bottle. The third UMeCeSSav article is the potassium hydroxide (KOH). The necessary artides are five. The first regarding the Bunsen burner is that the flame is missing. Likewise, in the drawing, the air and the gas are shut off, and consequently, cannot enter the burner. The clamp, the next necessary article, is t o be used to hold the flask in a n upright position. It is attached t o the stand and to the neck of the flask. In the last of the four wide-mouthed bottles the liquid should be water and not potncsium hydruxidr. The luunh articlc is the potaa\ium iudidc solution (KI , which is ured in l h c c of thc carbon rlirultidr (CS2.'. TI& potassium iodide snlutiun ic uied a 4 P test fur rhlc.rine. The iodine is set free 1,). Lhr chlorrne, and colors the sdution brown. Tu te,t the presen&. of iodine. 3.starch solution is nddrd to the pntnssiurn iodide solutiun and a characteristic blue coloration is produced, thereby proving the presence of iodine. The final articles are small pieces of rubber tubing. The wide-mouth bottles should be partly connected with glass and partly with the rubber connections. If a bottle or bottles were to be taken off, it could be done with ease if the partly rubber connections are used. If the connections would be all glass, separating one bottle fromthe rest would necessarily imply t h a t some chlorine gas wauld escape and as a consequence may cause h a m if a large amount of it was allowed to escape. The last division is intended t o show a bad result of the mistakes. If the thistle tube would not be immersed in the hydrochloric acid the chlorine gas wauld escape through it into the air and thus may cause serious harm to the experimentor. Another point under the miscellaneous gmup, which could likewise have been placed under the first division, has for its object t o show that, according t o the drawing, chlorine has no bleaching . effect whatsoever. In realitv, .. however, the colored cotton cloth should have had all the lines gone, since these lines are used t o show the presence of the coloring matter. The wet, colored cloth should be white, which will thereby show that chlorine has a bleaching power.
Other creditable criticisms were: The connecting tubes project too far into the bottles from which they conduct CI2. The tubing bends are represented as sharper than good glass-bending technic would render practical. Winners of one-dollar awards were: WILLIAM DISCAER, Kirkwood, Mo.; DOROTHY E. ANDERSON, Syracuse, N. Y.; RICHARD M. LEWIS, New Canaan, Conn.; FRANCIS STUEVE,Chicago, Ill.; BETTY STEPHENSON. Chattanooga, Tenn.
