Culture - Journal of Chemical Education (ACS Publications)

Culture. J. Chem. Educ. , 1929, 6 (10), p 1766. DOI: 10.1021/ed006p1766. Publication Date: October 1929. Cite this:J. Chem. Educ. 6, 10, XXX-XXX ...
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After a good vacuum has been produced the apparatus is heated from c to the top of the enclosed metal until the metal is molten-both metals melt below 100". The heating may be accomplished by a hand torch or by a furnace made by wrapping resistance wire around some glass tubing of sufficient diameter t o surround the apparatus or, if the lower tube be short, by immersing the apparatus in a bath of melted paraffin or Crisco. With the metal molten, stopcock e is closed and f opened slowly. The ammonia pressure forces the pure liquid into the slender tube, impurities (oxide, hydroxide, etc.) being caught by the constriction a t b.' Ammonia is not essential here, any relatively inert gas would do as well; even opening the stopcock to the air would be satisfactory although i t is better not to use a gas which reacts readily with the metal. This method of filling glass tubing with the alkali metals has been in use at Stanford University by Professor E. C. Franklin and his students for a number of years.% They used such tubes to introduce pure alkali metals into liquid ammonia solutions. Not only is the metal so added free from oxide and hydroxide but also the weight of metal for a given length of tubing is known. Provided the tubing has no great variation in bore diameter, it is easily calibrated by weighing a measured length before and after dissolving the metal in alcohol.

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Oftentimes it is desirable to place an iron nail or a short length of glass rod abovc the alkali metal to aid in breaking the oxide coating surrounding themetal. Bohart, a student of Dr. Franklin, describes a modification of this procedure [ J . Phys. Chem., 19, 539 (1915)l. A similar technic employed in a different connection has been used by Dr. Kraus and his students [Kraus. J . Am. Chem. Soc.. 30,1206 (1908); Smyth, Ibid., 39, 1299 (1917); Peck, Ibid., 40, 337 (1918); Krans and Lucasse, Ibid., 43, 2530 (1921); and other papers]. The same type of apparatus described in this article has been used t o cast sticks of tellurium [Kraus and Chiu, J. Am. Chem. Sac., 44, 2002 (1922)], tin [Bergstrom, J. Phys. Chem., 30, 16 (192G)I and sulfur [Bergstrom, I. A m . Chem. Soc., 48, 146 (1928)l.

Culture. To he a t home with those from all walks of life; to share the companionship of the great men and women of all literatures and of those who are near in the flesh; never to miss an opportunity of seizing upon a noble thought; t o get understanding from children and wisdom from bees, birds, and flowers; t o have ears that are open to the myriad harmonies of the world of nature and eyes that discern the manifold glories of the universe; t o worship a t the shrine of Beauty, he it enthroned in temple, grove, ripple of water, or haunting voice of wwdland bird; to cherish the remembrance of kindness rewived and t o pass it on to less fortunate than we; t o have a heart so attuned t o the infinite Compassion that no claim on it may be laid aside; t o hate no man but all sin; t o condemn no man unheard; to believe that the goad in man's soul is hut waiting t o he roused by the challenge of trust; t o he so endued with the spirit of patience as to abide steadfastly though humbly in the paths of righteousness and peace. -LINDA RIDER,Educ., 49, 570 (May, 1929).