Reaction of Sulphuric Acid. 247 



with absolute alcohol, one of the salts present in this mass is dis- 

 solved. On the solution of the other in water, and subsequent 

 crystallization, it proves to be the acetate of barytes. 



The salt dissolved in the alcohol does not appear susceptible of 

 crystallization, probably on account of its extreme solubility. On 

 drying it assumes a gummy appearance, and by still farther de- 

 siccation, may be obtained in the state of a dry mass destitute of 

 cohesion, and susceptible of being with facility reduced to the 

 state of a powder. 



When exposed to heat in a retort, this salt resists an elevated 

 temperature without alteration, but at length, if heated rapidly, 

 carbonizes, giving off sulphurous acid and a small quantity of essen- 

 tial oil and water. There remain in the retort a spongy carbona- 

 ceous substance, and a large quantity of sulphite of barytes. As 

 this result proved the acid united with the barytes to consist of 

 organic matter, combined with sulphuric acid and modifying its ■ 

 properties, in order to ascertain the quantity of the latter present, 

 barytes was precipitated by carbonate of potash, the precipitate 

 weighed and the resulting potash salt evaporated to dryness. It 

 was then intimately mingled with the black oxide of copper and 

 nitrate of potash, nitric acid added, and the whole mass gradually 

 heated to redness. Red fumes are given off during the whole of 

 the process, and while the nitric acid at the beginning of the ope- 

 ration prevents the deoxidation of any portion of the sulphuric 

 acid ; at the end, the oxide of copper prevents the explosive reac- 

 tion which would ensue, were nitric acid and nitrate of potash 

 alone present. 



The result of two experiments made in this manner, the 

 mass after ignition being washed with diluted chlorohydric acid, 

 and the solution precipitated by barytes, was as follows: — ■ 

 Carbonate of baryies 12^ gr's. Sulphate of barytes 16|- gr's. 

 Carbonate of barytes 13 i gr's. Sulphate of barytes I6i gr's. 

 The quantity of sulphuric acid as calculated from the quantity of 

 sulphate precipitated, is in each case, 5.59 gr's., while as calculated 

 from the precipitate of carbonate of barytes, on the supposition 

 that one atom of it is present in the barytes salt for each atom of 

 base, it would be 5 gr's. in the first instance, and 5.3 gr's. in the 

 second. It will therefore be perceived that in both experiments 

 the quantity of sulphuric acid, as calculated from the results, 

 exceeds the quantity necessary for forming an equivalent with 



