44 Wells, Wheeler and Penfield — Alkali-Metal 



Calculated 

 Analysis gave for CsBr 3 . 



Caesium 29'93 24-95 



Bromine 75*05 



The analysis corresponds with the formula CsBr 6 as well as 

 could be expected considering the great instability of the com- 

 pound. 



CsCl. CI J. 

 This substance can be prepared by dissolving 40 g. of caesium 

 chloride in a mixture of 600 c.c. of water and 200 c.c. of 

 concentrated hydrochloric acid, adding 30 g. of iodine (one 

 atom), passing chlorine to saturation, meanwhile keeping the 

 solution warm enough to dissolve any of the compound which 

 separates in the form of a yellow precipitate, and finally cool- 

 ing to crystallization. The hydrochloric acid is used to pre- 

 vent the simultaneous deposition of an acid caesium iodate. 



Calculated 

 Analysis gave. for CsCl . C1 3 I. 



Caesium 32*44 33-09 



Chlorine 34-79 35-32 



Iodine 31-11 31*59 



The crystals "are of a pale orange color. They are in the 

 form of slender prisms, usually in parallel position forming 

 plate-like groups. The body is sparingly soluble in water and 

 can be recrystallized from it without much decomposition. It 

 is nearly permanent in the air. On heating it is apparently 

 converted into CsCl . C1I, for it melts like that substance at 

 238° (uncorr.) in the open capillary tube. 



lib CI. CI J. 



This body can be conveniently prepared by adding 40 g. of 

 iodine to a nearly saturated solution of 38 g. of rubidium 

 chloride and passing in an excess of chlorine. The solution 

 becomes warm from the reaction, and on cooling large orange- 

 yellow plates' are deposited. 



Calculated 

 Analysis gave for EbCl . C1 3 I. 



Rubidium 24*12 23*63 24*11 



Chlorine 39*00 40*05 



Iodine 35*31 35*83 



The compound is soluble in alcohol, unaffected by ether. 

 When rapidly heated in an open capillary tube it melts at 

 213° (uncorr.) undergoing some decomposition, and becomes 

 completely white at about 270°. These numbers agree quite 



