128 



A STUDY OF THE ABSORPTION SPECTRA. 



uran>l bands, and the large uranyl blue-violet band. Besides these there is 

 a diffuse band at X 5300 and a band at X 6200 which broadens rapidly as 

 the depth of cell is increased. The uranyl bands are located as follows: 

 a, X 4980; b, X 4840; c, X 4680; d, X 4445 (weak band at X 4530); e, X 4300, 

 to /, X 4170. 



Uranous Chloride in Methyl Alcohol and Ether. 



Two photographs were made, one of uranous chloride in methyl alcohol 

 (next to the spark spectrum), and one of uranous chloride in a mixture of 

 about 60 per cent methyl alcohol and 40 per cent ether. Further addition 

 of ether caused a precipitate to be formed so that the absorption spectra 

 could not be obtained. 



The methyl alcohol solution showed complete ultra-violet absorption 

 to X 3700. The region X 4300 showed considerable general absorption due 

 to the blue-violet band. The following uranyl bands appear: i, at X 3880, 

 h, at X 4000, g, composed of two bands one at X 4110 and a narrow band 

 about 10 Angstrom units wide at X 4135, /, of two bands, X 4240 and X 4285, 

 the latter being quite narrow, d and e form one very broad band at about 

 X 4400, c at X 4610, and b at X 4780. Two bands, X 4930 (a) and X 5050 are 

 almost merged into each other. 



The addition of ether caused the absorption to increase; the ultra- 

 violet absorption extending to X 3800 and the absorption from X 4100 to 

 X 4450 being almost complete. The uranyl bands are slightly shifted 

 towards the red. Their general character remains the same. The wave- 

 lengths are approximately, i, X 3890, h, X 4010, g, X 4110, /, X 4260, de, 

 X 4440, c, X 4630, b, X 4790, a, X 4960, and a band at about X 5050. 



The effect of ether is to cause the bands to shift slightly to the red 

 and to increase the amount of absorption. 



Effect of the 

 A spectrogram was 

 chloride in water (strip 

 acid until the depth of 

 12.5 mm. (strip 3), and 

 The effect of hydro 

 the uranyl and uranous 

 appear much stronger, 

 broad, and the X 6655 

 reverses the appearance 

 red at the same time, 

 hydrochloric acid: 



Presence of Acids on the Uranous Bands. 

 made of a 3 mm. solution of 0.17 normal uranous 

 1). To this was added very strong lrydrochloric 

 cell was 6 mm. (strip 2), and finally until it was 



24 mm. (strip 4). 



chloric acid is very marked. In general it shifts 



bands to the red. It causes the uranyl bands to 



In an aqueous solution the X 6400 band is very 

 band comparatively narrow. Hydrochloric acid 



of these two bands; shifting both towards the 

 The following wave-lengths give the effect of 



