Chemical Constitution of Saline Solutions. 



279 



PART III. 

 The Action of Heat on the Absorption Speutra of Chromium Salts. 



Green Chromium Chloride. — Thin wedge- 

 cell. Gas liglit. 



A solution of CrjOj'ieHaO in hydro- 

 chloric acid. Not precipitable by 

 ammonium oxalate. 



At 20° 



At 100° Liquid nearly opaque, 

 measurements possible. 



No 



Chromium Sulphate, Cr23(S04)'15H20. — 

 Blue or violet salt. Thin wedge-cell. 

 Deep blue solution. 



Green Chromium Sulphate, 

 Cr23(S04)-5H30.— Produced from the 

 violet salt by heating to 100°. 



Violet Chromium Sulphate, 

 Cr23(S04)-15H,0.— 0-5 gr. in 4 c.c. of 

 H,0. 



Green Modification, Cr23(SOi)-5H30. — 

 0-5 gr. in 4 c.c. of H^O. 



C/iromic Nitrate, Cr(N03)3-9B[cO.— Vio- 

 let coloured salt. 



At 20° Spectrum begins a little below 



B, X 687, . 



Rays transmitted to 



Absorption Band, . 



Bays transmitted to 



At 100° Spectrum begins at 

 Rays transmitted to 

 Absorption Band, 

 Spectrum ends at 



(See figs 3 and 4, Plato XXI.) 



At 1 6° Rays transmitted from . 

 to . 

 No well defined spectrum. 



At 16° Spectrum begins at 

 Rays transmitted to 

 Absorption Band, 

 Spectrum ends at 



At 100° Spectrum begins at 

 Rays transmitted to 

 Absorption Band, 

 Spectrum ends at 



At 16° Spectrum begins at 

 Rays transmitted to 

 Absorption Band, 

 Spectrum ends at 



At 1 6° Spectrum begins ut 

 Rays transmitted to 

 Absorption Band, 

 Spectrum ends at 



At 50° Spectrum begins at 

 Rays transmitted to 

 Absorption Band, 

 Spectrum ends at 



At 100° A little light transmitted be- 

 tween .... 

 (See figs. 1 and 2, Plate XXI.) 



2 Q2 



691 



610 



610 to 566 



475 



666 



627 



627 to 573 



497 



520 

 465 



662 



562 



562 to 525 



423 



662 



577 



577 to 526 



444 



662 



575 



575 to 526 



442 



715 



627 



627 to 557 



449 



715 



627 



627 to 557 



464 



548 & 500 



