286 P. T. Walden — Double Chlorides and Bromides, etc. 



alkalimetry. Water was determined by combustion behind 

 sodium carbonate and absorption in a washed calcium chloride 

 tube. With (XH^FeClgH^O the water was removed by sub- 

 jecting the salt to a temperature of 150° C. in an air bath for 

 one hour. 



The DoiLble Chlorides. — These salts are all red except 

 CsFeCl 4 iyH 2 which is straw yellow. There is a distinct grada- 

 tion in the shades of the salts of the type 2 : 1 from (NH 4 ) 2 Fe 

 C1 B H„0 which is a deep ruby red, growing lighter through 

 the caesium, rubidium and potassium compounds until the last 

 is very nearly the color of potassium dichromate. 



3:1 Ccesium Ferric Chloride, Cs^FeCl^HJ). — This salt is 

 the only one of the 3 : 1 type which was prepared in the 

 present investigation. It separated from a solution containing 

 50 gr of caesium chloride and- from -5 gr up to 2-5 gr of ferric 

 chloride. The following analyses were made from separate 

 crops : 



Calculated for 

 A. B. C. CssFeCleHoO. 



Caesium 58-30 58-42 58-17 



Iron _. 7-91 7'85 8'17 



Chlorine 30*87 30-82 30-98 31-01 



Water 2-74 2-72 2-64 2*65 



99-82 99-81 



100-00 



In color it closely resembles sodium dichromate. It is well 

 crystallized in small prisms which are arranged in compact 

 clusters radiating from a center. 



2:1 Ccesium. Rubidium, Potassium and Ammonium Fer- 

 ric Chlorides, Cs 2 FeCl b H 2 0, Rb 2 FeCl b H 2 0, KJFeCl.E^O and 

 {NS^FeC^IIJJ. — If solutions of the several alkali-chlo- 

 rides, containing 50 gr each be made, it is necessary to add 

 3 gr of ferric chloride to make the caesium salt of this type, 

 10 gr to make the rubidium salt, 15 gr to make the potassium 

 salt and 70 gr to make the ammonium salt. The caesium, 

 rubidium and potassium compounds can be recrystallized 

 unchanged, although with the last two there is a tendency to 

 separate simple alkaline chlorides at the same time. Several 

 separate crops were analyzed of each salt with the results shown 

 below. 



Csesium 



Iron . _ 



A. 



51-15 

 11-05 



B. 

 51-05 

 10-98 

 34-19 



3-59 



C. 



34-02 



Calculated for 

 Cs. 2 FeCl 5 H 2 0. 



51-40 

 10-82 



Chlorine 

 Water 



34-36 

 3*55 



34-30 

 3-48 



100-11 



99-81 



100.00 



