# Followup silver chloride & ammonia question



## warrendya (Jul 31, 2008)

I had some silver chloride I believed mixed with lead chloride I wished to separate. I added some 50/50 houshold ammonia and water, mixed, and let it settle overnight. In the morning there was definitely less precipitate in the beaker, but there was also what looked like silvery metallic flakes floating on the surface. Any idea what those might be?

Dan


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## eagle2 (Aug 6, 2008)

Dan, I`ve seen that many times. Some type of silver crystals salt is my guess. Just stir the solution and most of them will dissolve in again. Adding more ammonia also works. 

Also DO NOT let the solution dry out or stand for a long period. Silver forms Very Dangerous Explosive compounds this way.

Al


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## Shecker (Aug 6, 2008)

The removal of lead chloride only involves the use of water heated to 180 degrees F. That makes lead chloride water soluble. As the solution cools lead chloride will re-crystallize. There is no need to form potentially explosive compounds.

Randy in Gunnison


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## eagle2 (Aug 6, 2008)

Randy has the better method, since Lead Chloride aslo tends to dissolve in alkali hydroxides, including Ammonia. 

Looking in my Merck index PbCl2 is soluble in 93 parts cold water, 30 parts of boiling water (as an example this means 1gm in 93ml cold water). AgCl solubility is much less. 1.93mg per Liter at 25C.

Also remember, PbCl2 is Poisonous, and can be absorbed through the skin.

Al


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