Subject: Re: [DCHAS-L] Iodine
corrosivity
Date: September
24, 2009 4:09:29 PM EDT
If the metal trap is galvanized iron, meaning
zinc-coated, certainly zinc will react spontaneously with I2 in a redox
reaction giving Zn2+ and iodide, I- . The same thing can happen
with aluminum, with similar chemistry.
Wayne
Wolsey
Professor
Emeritus
Macalester
College
St. Paul,
MN
===
Subject: Re: [DCHAS-L] Iodine
corrosivity
Date: September
24, 2009 5:39:12 PM EDT
Linda,
Based on
the observed results, elemental iodine will corrode a metal trap. A
knowledge of basic descriptive chemistry, as it was once taught, bears
this out. There are a couple of things wrong here, not the least of
which was an incorrect disposal method. A plumber should have been
called to remove and clean the trap. His visit would be followed by
proper disposal of the residue. If this couldn't have been done and as a
last effort, the teacher perhaps should have known that iodine is much
more soluble in a solution of potassium iodide than in water. On the
other hand, is it preferable to have a leak with its obvious local
contamination followed by proper disposal of the residues than it
is to discharge a (significant) amount of iodine and KI into the sewer
system?
Regards,
Ernest
Lippert
===
Subject: Re: [DCHAS-L] Iodine
corrosivity
Date: September
25, 2009 10:57:28 AM EDT
Certainly a possibility. Might be interesting to
perform surogate experiments w/iodine crystals and pieces of pipe
metal. Do the experiment w/iodine crystals, w/whatever else might have
gone down this drain, and then w/iodine crystals plus whatever else
might have gone down the drain.
Bob
