Plante1999:
See my reference on Silver Chlorate formation. Here is another one:
Source: "A comprehensive treatise on inorganic and theoretical chemistry, Volume 2, by Joseph William Mellor, page 271. To quote:
"L. N. Vauquelin found that when chlorine acts on silver oxide diffused in water, a mixture of silver chloride and chlorate is formed, and it was
accordingly supposed that these same products are obtained when chlorine acts on the salts of silver. The products observed by L. N. Vauquelin were
shown by A. J. Balard to be end products, being preceded by the formation of silver hypochlorite. According to A. J. Balard, finely divided silver
immediately decomposes hypochlorous acid with the evolution of oxygen, and the formation of silver chloride. Again, if an alkali hypochlorite be
treated with silver nitrate, or if silver oxide, Ag20, suspended in water, be treated with chlorine, much heat is developed and silver chloride and
silver peroxide are precipitated while a liquid with bleaching properties is formed. The liquid is very unstable, and decomposes in a few minutes with
the separation of silver chloride and the formation of a soln. of silver chlorate which does not bleach. If an excess of chlorine be employed, all the
silver is precipitated and a soln. of hypochlorous and chloric acids remains. If an alkali hydroxide be added to the bleaching liquid, oxygen is
evolved, and a mixture of silver chloride and peroxide is precipitated. Similar results are obtained if an aq. soln. of silver chlorate, nitrate, or
acetate be employed except that the corresponding acid is liberated. J. S. Stas has •shown that probably no chloric acid or silver chlorate is
formed in the primary reaction:
Ag20+2Cl2+H20=2AgCl+2HCl0
If the silver oxide or carbonate be in excess, the silver oxide gradually forms silver hypochlorite,
2HOCl + Ag20 =2AgOCl+H20
which is readily soluble, and the soln. is stable so long as it is shaken with the excess of silver oxide present. This salt is partially decomposed
on standing in darkness, and completely decomposed at 60° into silver chloride and chlorate:
3AgOCl=2AgCl+AgCl03
and the latter remains in soln. in the alkaline liquid. J. S. Stas found no signs of the formation of perchloric acid. F. Raschig prepared silver
hypochlorite by the action of alkaline sodium hypochlorite on silver nitrate, and also by adding a soln. of silver nitrate to sodium azide, NaN3, or
to a soln. of chloroazide in sodium hydroxide."
LINK:
http://books.google.com/books?pg=PA271&lpg=PA271&dq=...
So the formation of Silver Chlorate is apparently not slow and one can actually visibly observe the formation of the AgCl. I suspect that AgClO3
should be quickly be employed in a reaction, or dried per the directions, as the aqueous solution is most likely not stable. In fact, Mellor (cited
previously), page 340, notes that AgClO3 decomposes into AgCl and O2 in the presence of HCl, HNO3 and even Acetic acid. Chlorine also reacts forming
AgCl, HClO3 and O2.
To comment on why one would not try to make AgClO3 as the soluble salt of choice is that only 1/3 of the Silver metal is converted into a soluble
salt.
In addition to the aqueous stability issue of AgClO3, the generally slow dissolution of Silver metal itself into a salt and the cost of the acids, the
main issue of say large scale production of, for example KClO3 (by adding KCl to AgClO3), remains the inherent cost of the Silver itself even with
recycling.
[Edited on 16-1-2012 by AJKOER] |