Re: CS>basic dumb question
From: Mike Monett
Date: Fri, 25 Mar 2005 04:28:54
Background
~~~~~~~~~~
Earlier, I posted the results of an experiment to determine the
solubility of silver hydroxide in dw. The conclusion is silver
hydroxide is insoluble:
http://escribe.com/health/thesilverlist/m78851.html
Silver hydroxide is formed during silver electrolysis and when cs
evaporates. The equation is
Ag(+) + OH(-) --> AgOH
It is black or dark brown, and can decompose under pressure to
produce silver metal and oxygen.
Contrary to recent statements, silver hydroxide is stable at
temperatures under 100C, where it decomposes to silver metal and
oxygen.
It is easy to distinguish between silver hydroxide (AgOH) and silver
oxide (Ag2O) since silver oxide decomposes at 300C (572F).
Procedure
~~~~~~~~~
To generate silver hydroxide for this experiment, I repeated the
experiment described above. When the cathode was covered with a
black coat, I removed it and let it dry. The appearance changed a
little but not much.
The rod was placed on a hot plate under a stereo zoom microscope. A
thermometer was used to determine the temperature.
As the hot plate began to heat up, it was obvious where the heating
elements were located. The 12ga silver rod turned from black to gray
each time it crossed the spiral element. The thermometer read only
160 degrees F when the pattern began appearing. It was very clear at
180F.
When the thermometer reached 210 degrees F, the rod was completely
gray. No black coating remained.
I removed the rod with pliers and let it cool in the air. When cool,
I wiped it with a tissue. The tissue had a small spot of shiny
silver metal where it touched the rod.
I wiped the anode rod, that had not been heated, with the same
tissue. It left a black patch with a small shiny spot in the middle.
Conclusion
~~~~~~~~~~
The conclusion is the black coating produced by electrolysis and the
evaporation of cs is silver hydroxide, AgOH.
Reference
~~~~~~~~~
I previously located a MSDS for AgOH that stated the decomposition
temperature of 100C, but unfortunately lost it and all references to
silver hydroxide seem to have disappeared from the web. The only
reference I can find that mentions the decomposition temperature of
AgOH is below. It states 250F instead of 212F:
http://encyclopedia.jrank.org/SHA_SIV/SILVANUS_Lat_silva_wood_.html
Mike Monett
--
The Silver List is a moderated forum for discussing Colloidal Silver.
Instructions for unsubscribing are posted at: http://silverlist.org
To post, address your message to: [email protected]
Silver List archive: http://escribe.com/health/thesilverlist/index.html
Address Off-Topic messages to: [email protected]
OT Archive: http://escribe.com/health/silverofftopiclist/index.html
List maintainer: Mike Devour <[email protected]>
