l82&rf contained in Sea Water. ' 415 



into an acid deutobromate. When put into hot liquid sulphuric 

 acid, this compound liquefies, and remains at the bottom of the 

 acid, having the appearance of oily drops, and without suffering 

 any sensible alteration. Nitric acid, on the contrary, soon 

 occasions a rapid disengagement of brome ; the deutobromuret 

 6f tin, analogous to the fuming liquor of Libavius, it will be 

 observed, possesses but few of the properties of this latter com- 

 pound. 



Bromurets of Mercury. 



Mercury combines with brome in several proportions. ^ 

 solution of an alkaline hydrobromate, acting upon protonitrate 

 of mercury, occasions the formation of a white precipitate^ 

 resembling protochloride of mercury, and which appears to be a 

 protobromuret of the metal. 



Brome attacks mercury strongly ; the combination is effected 

 with the extrication of heat unaccompanied by light. The result 

 is a white substance, which sublimes when heated, and which is 

 soluble in water, alcohol, and especially in ether, it is precipita* 

 ble red and yellow by the alkalies, and offers many analogies 

 with corrosive subHmate. It is distinguished by the red vapours 

 of brome which it yields, when treated with nitric acid, and still 

 better by the sulphuric acid ; the advantage of using the latter 

 acid appears to me to depend upon the possibility of employing 

 a higher temperature. 



Bromuret of Silver, 



Nitrate of silver produces a curdy precipitate of bromuret of 

 silver in the solutions of the hydrobromates. This compound is 

 of a canary yellow colour when dried in the dark ; but if exposed 

 while moist to the light, it blackens, but not so quickly as the 

 chloride of silver; like this substance also it is insoluble in 

 water, and soluble in ammonia. Nitric acid produces no effect 

 upon it even when boiling, but sulphuric acid disengages vapour 

 of brome when boiling. Nasent hydrogen decomposes it, and 

 there are produced metallic silver and hydrobromic acid, and I 

 .employed this method to analyze the bromuret of silver ; I 

 introduced a certain quantity of it into a mixture of pure granu- 

 lated zinc and dilute sulphuric acid; the silver was reduced, 

 .and I weighed the silver after ascertaining that the zinc had 

 J)een completely dissolved; the mean of two experiments,, which 

 differed but very little from each other, gave us the composition 



Silver 589 



Brotiie. . , 411 



1000 

 This gives 94*29 as the atomic weight of brome, which does no*t 



