According to theory, solubility of silver bromide in water is 0.14 mg/L. So, the quantity of water is very large, with small amount of silver bromide. My question, is there any method or techniques to dissolve silver bromide with less amount of water, for example in 100ml of water?
Silver chloride is known to be significantly more soluble in hot water than in cold water. Probably the same is true for silver bromide, but I couldn't find actual data.
In any case, even if you use hot water, (a) the dissolution is likely to take a long time, and (b) most of the salt will reprecipitate on cooling. If you do the experiment make sure the suspension stays in the dark because silver halides are photosensitive.
If you just want to bring AgBr into solution and don't mind the presence of a complexant you can use a variety of complexants, such as thiosulfate.
You might want to add ammonia or KCN; both from complexes with Ag+. I would not recommend thiosulfate, because that can reduce Ag+ to metallic silver, which is not soluble in water.
Mohd ZULFADLI Adenan
To dissolve silver bromide in 100 ml you need to take 0.014 mg.
Hi Ulrich Deiters
Actually sodium thiosulfate is a very common way of dissolving AgBr (in photography, where confusingly it is called "hypo") by forming a soluble complex. If you want a solution with a long shelf life though this may not be the best, because on heating or over time thiosulfate releases sulfide which gives the black insoluble Ag2S. For stability ammonia or (with your safety officer thoroughly tied down) cyanide are probably preferable indeed.
Emanuel Cooper thanks for the sharing and theoretical input, one next question, can you please specify the ideal weight of thiosulphate, the volume of water and the weight of silver bromide in order to dissolve all in water. Also, how long the solution need to be stirred to ensure the dissolution of all chemicals. Thanks a lot also to Yuri Mirgorod and Ulrich Deiters for your sharing and meaningful feedback.
Hi Mohd ZULFADLI Adenan
I have no firsthand experience with photographic development and fixing, but my understanding is that the common practice for "fixing" (that is the removal of excess silver halide after development) is to use 15% sodium thiosulfate. See discussion in https://www.largeformatphotography.info/forum/archive/index.php/t-75801.html
Much lower concentrations will also work. For instance, in the spot test for the detection of thallium in the presence of silver, thallium(+) as well as silver are precipitated with potassium iodide as the yellow iodide(s) out of a drop of sample solution. When a precipitate appears, 1-2 drops of 2% sodium thiosulfate are added; a yellow precipitate insoluble in the thiosulfate solution indicates thallium. (From Fritz Feigl, "Spot tests in inorganic analysis", 5th English edition (1958), p. 155)
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