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Partial use of powdered chemicals

Posted: Sun Apr 02, 2006 11:50 pm
by leecrump
have been partially using packages of powdered chemicals for about 6 months now. I have had no problems. I feel this practice has given me better shelf life and a more chemically stable way to store reagents that I am not ready to use just yet. I have heard from several sources, including this forum, that partial use of powders will cause problems due to the uneven distribution of chemicals within the packaging. The last several sources I?ve asked have, themselves, not experienced this problem.
I would like to hear from people who have had first hand problems from the partial use of powered chemicals.

As always thanks for the info.

Re: Partial use of powdered chemicals

Posted: Tue Apr 04, 2006 4:25 pm
by Ornello
leecrump wrote:have been partially using packages of powdered chemicals for about 6 months now. I have had no problems. I feel this practice has given me better shelf life and a more chemically stable way to store reagents that I am not ready to use just yet. I have heard from several sources, including this forum, that partial use of powders will cause problems due to the uneven distribution of chemicals within the packaging. The last several sources I?ve asked have, themselves, not experienced this problem.
I would like to hear from people who have had first hand problems from the partial use of powered chemicals.

As always thanks for the info.
This is not a good practice. The amounts of the chemical constituents in a developer are quite different, and there is no way to be sure that any given sample of the contents is representative of the whole. In fact, it is practically impossible for it to be so. Always dissolve the entire contents of any powdered developer. The developer will work, but there will not be consistency from one mix to the next.