34:8 Browning and Flint — Complexity of Tellurium. 



Ninety-two grams of this pure product were converted to 

 tetrachloride and the solution, in as small amount of hydro- 

 chloric acid as possible, was diluted with four liters of boiling 

 distilled water, and cooled. The precipitate, seventy -six grams 

 of pure white, crystalline Te0 2 , was removed and the filtrate 

 was heated again to boiling, after which ammonia aud then 

 acetic acid in the smallest possible excess were added. When 

 cold, thirty-eight grams of Te0 2 were obtained, more finely 

 crystalline than the preceding fraction, but also pure white. 

 The filtrate from this fraction contained no tellurium detecta- 

 ble by stannous chloride, and was consequently discarded. 



These two fractions were next separately refractionated by 

 an exact repetition of the process above described, each frac- 

 tion secured being likewise refractionated, the three fraction- 

 ations thus providing eight fractions, of which the last, about 

 1*5 gram, was set aside. Fraction two was combined with 

 three, four with five, and six with seven, and each portion of 

 the material refractionated, as was also fraction one. From 

 this point on, the fractionation was carried out after the usual 

 plan of fractional crystallizations, intermediate fractions being 

 combined before retreatment, and those at the latter end of 

 the series being removed when small in amount (from one to 

 two grams). In this manner ten fractionations were per- 

 formed, as a result of which were secured about fifty-nine 

 grams of dioxide from the first, or water, end, and fifteen 

 grams from the last, or ammonia-acetic acid, end of the series. 

 Each of these portions was refractionated once, the water 

 fraction (50 grams) of the first being denominated alpha, and 

 the ammonia-acetic acid fraction (13 grams) of the latter, beta. 

 The alpha and beta fractions were lastly converted to basic 

 nitrate, the former by one and the latter by two crystalliza- 

 tions, according to the method described by N orris, Fay, and 

 Edgerly.* It is to be noted that in the process of fractiona- 

 tion the material of each fraction had been crystallized out of 

 a large amount of distilled water. 



The alpha and beta fractions were subjected to analysis by 

 three different methods : (1) the basic nitrate method ; (2) the 

 Gooch and Danner modification of Brauner's permanganate 

 process ;f and (3) the ammonia-acetic acid method previously 

 described. 



(1) After bringing the basic nitrate to constant weight at 

 140° as recommended by N orris,:); carefully weighed portions 

 were heated in platinum with a gradually increasing tempera- 

 ture for a period of iive to six hours. The crucibles were con- 

 tained in porcelain radiators, a porcelain dish being supported 



* Am. Chem. J., xxiii, 105. f This Journal, xliv, 301. 



X J. Am. Chem. Soc, xxviii, 1675. 



