52. Reactions in presence of Nickel : (a) Inability of 

 nitrogen and hydrogen to combine in presence of iron 

 and nickel. (&) Reduction of the oxides of nitrogen, 

 sulphur and phosphorous in presence of nickel. 



By Panchanan Neogi, M.A., Professor of Chemistry, Rajshahi 



College, and Birendra Bhusan Adhicary, M.A. 



The interesting problem of combining nitrogen and hydrogen 

 directly to form ammonia has long been attracting the atten- 

 tion of chemists. Donkin (Proc. Roy. Soc. 21, 281) has succeeded 

 in obtaining traces of ammonia by passing electric sparks or 

 silent discharge through a mixture of nitrogen and hydrogen 

 in the proportion of 1 : 3. This has been further studied by 

 Morren (Compt. Rend. 48, 432), Perrot (Compt. Rend. 49, 204) 

 and Chabrier (Compt. Rend. 75, 484). Johnson (Trans. Chem. 

 Soc. 39, 128) showed that he obtained ammonia at the rate 

 of -0059 grams per hour by passing over spongy platinum 

 at a low red heat a mixture of hydrogen and nitrogen, the 

 latter being prepared from ammonium nitrite and freed from 

 nitric oxide by passing it through ferrous sulphate solution. 

 L. Wright (Trans. Chem. Soc. 39, 257) pointed out that ferrous 

 sulphate is unable to absorb all the nitric oxide evolved along 

 with nitrogen, that the ammonia obtained by Johnson was due 

 to the reduction of nitric oxide and not to the combination of 

 nitrogen and hydrogen. In fact Wright (loc. cit., p. 131) him- 

 self admitted that he did not get ammonia by using nitrogen 

 prepared from air or the same gas obtained from ammonium 

 nitrite and purified from the accompanying nitric oxide after 

 passing the gas over red hot copper. Ramsay and Young 

 (Trans. Chem. Soc. 45, 93) have remarked that they obtained 

 small quantities of ammonia by passing a mixture of hydrogen 

 and nitrogen over red hot iron filings. The details of their ex- 

 periment and the method of purification of nitrogen and iron 

 are not given in the paper, but their experiment has been em- 

 bodied in Ramsay's System of Inorganic Chemistry. As reduced 

 nickel has now been largely employed as a catalytic reducing 

 agent in organic chemistry since Sabatier and Seuderens' time, 

 we thought that nitrogen and hydrogen might combine in pre- 

 sence of nickel to a much greater extent than in the presence 

 of iron. We therefore repeated Ramsay and Young's experi- 

 ment, taking every possible precaution to remove nitric oxide, 

 and found that nitrogen and hydrogen do not combine in pre- 

 sence of iron free from carbon. We also found that the two 

 gases do not combine in presence of nickel also. 



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