Name: Gabe and Joanna
Status: student
Grade: 9-12
Location: TN
Country: USA
Date: Winter 2011-2012
Question:
I am preparing a thesis for my science project. Do different kinds of salts speed up the iron oxidation process at different rates than other salts? If so, what qualities of salt would make conditions best for rusting?
Replies:
The reasons you have not found a lot of information on iron rusting
is because it is a very complicated process. Many factors play a role:
1. The chemical identity of the salt, the concentration of salt,
concentration
of dissolved oxygen, which in turn depends upon the identity of the salt and
its concentration.
2. The temperature and time of the exposure.
3. The specific kind of iron. Most industrial "iron" is in fact an
alloy, and some
alloys are more (or less) resistant to corrosion than others. So "iron" does
not adequately describe the metal being tested.
4. The pH of the test solution must be buffered because the
corrosion reaction can change the pH
which in turn affects the rate of rusting.
This is the "short" list. You need a research "plan" to figure if
and how well you can control the many variables that may come into play. As
you have described the experiment, you may be heading into results that will
be difficult to interpret.
NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.
