SPECTROPHOTOGRAPHY OF CHEMICAL REACTIONS. 69 



latter being dissolved in 2 parts of water and 3 parts of methyl alcohol in 

 strip 1 ; in 1 part water and 1 part methyl alcohol in strip 2, and in pure water 

 in strip 3. Strips 4, 5, 6 represent the absorption of uranous chloride in equal 

 parts of water and methyl alcohol, to which potassium nitrate is added; in 

 strip 4, potassium nitrate is in 2 parts water and 3 parts of methyl alcohol, 

 strip 5 in equal parts of water and methyl alcohol, and in strip 6 in pure water. 

 The last strip represents the absorption of uranous chloride in equal parts of 

 water and methyl alcohol. This spectrogram indicates that the action of the 

 calcium and potassium nitrates may be that of driving back the amount of 

 hydrate in equilibrium with the alcoholate, and that by increasing the pro- 

 portion of water present in the solution the amount of hydrate present is 

 increased at the expense of the alcoholate. 



THE REDUCTION OF URANYL SALTS IN SOLUTION. 



The reduction of uranyl to uranous salts deserves a thorough study, and 

 undoubtedly offers a fertile field for investigation, and this partly on account 

 of the light that quantitative spectrophotography will probably throw upon 

 the subject. In certain solvents some interesting results have already been 

 obtained. In the case of an ether solution of uranyl chloride it was found that, 

 on the addition of zinc and hydrochloric acid, three phases resulted an oily 

 and extremely concentrated solution of uranous chloride formed at the bottom; 

 a much more dilute solution of uranous chloride which was above the oily 

 layer and which, on standing, gave up its uranous salt to the oily liquid 

 below; and the upper layer, which only contained uranyl chloride in solution. 

 These three liquid layers were completely separate from one another. When 

 the whole system was thoroughly shaken and allowed to stand, the three 

 strata soon separated again from one another. 



Uranyl chloride dissolved in isobutyl alcohol, to which zinc and strong- 

 hydrochloric acid are added, also shows the formation of an oily and dense 

 liquid, which was almost opaque on account of the large amount of uranous 

 chloride dissolved in it. These very concentrated solutions of uranous salts 

 would serve admirably for low-temperature work, and for the detection of 

 the Zeeman effect. 



When hydrochloric acid is added to a solution of uranyl chloride in propyl 

 alcohol, the two solutions mix. Zinc is then added and the reduction takes 

 place very slowly. 



A, plate 26, represents the absorption spectrum of the uranous chloride 

 solution in ether, to which some hydrochloric acid had been added. The 

 absorption spectrum is quite characteristic, and shows some new bands. 

 Several of these bands are quite sharp and narrow. As an example, there is 

 a band near X 5000 that is quite strong and is only about 25 Angstrom units 

 in width. 



REDUCTION OF URANYL CHLORIDE IN METHYL ESTER. 



To a solution of uranyl chloride in methyl ester were added hydrochloric 

 acid and metallic zinc. The hydrochloric acid does not mix with the ester 

 solution. For a considerable time hydrogen is given off, the ester solution 

 remaining of a greenish-yellow color. Quite suddenly, however, the ester 



