116 



Va7i Name and Broion — Tri-lodide and 



kin's work with bromides of the alkali metals, is 0'0623. 

 Evidently cadmium bromide, cadmium potassium bromide, 

 CdBr.2KB2r, and mercuric potassium bromide, HgBr2.2KBr2, 

 like the corresponding iodides, must be classed as abnormal. 

 The same thing is no doubt true of mercuric bromide, though 

 the low solubility of this salt made the experiments difficult 

 and the results inaccurate."^ 



Table XI. 









Cadmium 



Bromide. 







1. 



T = 0-1556 molar CdBrj. 



2. a 



= 0-0610 molar CdBr^. 



(5;Br) + (2Br3) = 2rt = 0-3112 molar. 



(2Br) + 



SBrg) - 2a = 0-122 molar. 



h 



9 



c 



K^ 



h 



9 



c K^ 



83-6 



965 



30-6 



0-157 



51-7 



883 



30-4 0-128 



41-0 



437 



28-8 



0-168 



27-94 



432-0 



28-8 0-12 



22-12 



229-8 



28-0 



0-175 



14-80 



218-0 



28-0 0-12 



10-85 



105-7 



27-6 



0-166 



7-77 



108-7 



27-6 0-122 



5-07 



48-1 



27-4 



0-163 



3-673 



46-6 



27-4 (0M04) 



2-533 



24-21 



27-3 



0-167 



1-823 



25-05 



27-3 0-123 



1-319 



14-08 



27-2 



(0-139) 



0-934 



12-91 



27-2 0-126 



0-598 



5-65 



27-2 



0-165 



0-469 



6-56 



27-2 0-129 







mean 



0-165^ 



0-2239 



3-198 



27-2 0-135 













mean 0-127^ 



Table XI. 



(continued) 





Table 



XII. 



3. 



= 0-0882^ 



' molar CdBra. 



Mercuric Bromide. 



(2Br) + 



(Brs) = 2a 



= 0-076 



5 molar. 



a = 



0-01447 molar HgBrs. 



h 



Q 



c 



i^i 



(2Br) + (^ 



Brs) = 2a 



= 0-02894 molar. 



61-3 



1268 



31-7 



0-104 



h 



Q 



c K, 



13-45 



230-6 



28-0 



0-113 



26-97 



797 



30-0 1-8 



13-03 



223-4 



28-0 



0-113 



10-71 



300-4 



28-5 1-8 



6-15 



102-0 



27-6 



0-111 



6-53 



178-7 



28-0 1-2 



3-408 



56-0 



27-4 



0-112 



4-16 



113-5 



27-6 2-4 



1-655 



27-04 



27-3 



0-113 



2-664 



72-5 



27-6 2-1 



mean 0-111, 



mean 1-8, 



■^Herz and Paul (Zeitschr. anorg. Chem., Ixxxr, 214, 1914) have also 

 studied the equilibrium between bromine and mercuric bromide at 25°. 

 Their results, recalculated on the same basis as our own, are as follows : 



(2Br) + (2Br3) 



(2Br3) 



(Br,) 



(2 Br) 



Ka 



39-98 



0-9 



8-1 



39-08 



0-352 



42-4 



0-8 



7-6 



41-6 



0-395 



39-46 



0-7 



7-0 



38-76 



0-388 



39-46 



06 



6-5 



38-86 



0-421 



42-4 



10-6 



212-5 



31-8 



0-638 



The last determination was not included in the original table of Herz and 

 Paul, but has been calculated from data, given elsewhere in their article, for 

 the solubility of bromine and of mercuric bromide in water saturated with 

 both. Though their values of -^i are smaller throughout than ours, they 

 also show great abnormality in the behavior of mercuric bromide. 



