T II E 

 LONDON, EDINBURGH and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[THIRD SERIES.] 



FEBRUARY 1841. 



XV. On ilie Comhination of Hydr cited {the Hydrate of) Sul- 

 phuric Acid xoith Nitric Oxide. By M. Adolph Rose*. 

 T^HERE has frequently occurred of iate in commerce, a sul- 

 ^- pliuric acid which is more or less contaminated by one of 

 the oxides of nitrogen, and which, treated with a solution of 

 copperas, {eisenvitriol) gives at times a dark red, at times a 

 blackish-brown colouring. It is usually considered as con- 

 taminated by nitric acid, which is said to originate, partially 

 by the decomposition of the white crystals, which are frequent- 

 ly, or almost always formed in larger or smaller quantities in 

 the leaden chambers f, partially by the oxidation of the nitrous 

 acid in the chambers. Those crystals consist, according to 

 Gaultier deClaubry and Henry, of sulphuric acid, nitrous acid 

 and water, and are stated to be decomposed on solution in wa- 

 ter, into sulphuric acid, nitric acid, and evolving nitric oxide. 

 This, even though slight, amount of nitric acid, in English 

 sulphuric acid of commerce, is very injurious in the prepara- 

 tion of hydrochloric acid, as on the employment of such an 

 acid a chloriferous hydrochloric acid is constantly obtained. 



To purify the sulphuric acid from the nitric acid and sul- 

 phate of lead, it is usually subjected to distillation. On the 

 distillation of a sulphuric acid which gave a strong colouring 

 with copperas, I changed the receiver, as in this, according 

 to almost all works on chemistry :{:, the water and nitric acid 



* From Poggendorfl's Aiiualcn,vo\. 1. p. IGl. Translated and commu- 

 nicated by Mr. \V. Francis. 



t [A paper on tlic com|)osition of these crystals and on the relations of 

 tlicir formation in tiie manufacture of suiiihuric acid, hy Dr. S. L. Dana, 

 api)earcd in Lond, and Kilinb. Pliil. Mag., vol. iii. p. 1 10'. — Edit.] 



I Geigcr's Pharmacie, latest edition, p. 273. — Mitschcrlich's C/icmir, 

 p. 480. 



rhil. Mag. S. 3. Vol. 18. No. 11 J. Feb, 1811, G 



