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Will peroxide rust iron nails?

Q. Hi,

I am doing a science project for school and my question is what makes Iron nails rust faster water (h2O) or hydrogen peroxide 3%) [affil links] (h2o2)? I am asking this because oxygen mixed with iron makes things rust since hydrogen peroxide has 2 molecules of oxygen maybe it will make the iron nails rust faster.

Deborah M. [last name deleted for privacy by Editor]
student - lakeland, Florida
2003

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A. This should be a good experiment, Deborah!

Advice first: in chemistry, all the different elements are abbreviated with either a single capital letter or a capital letter followed by a small letter. You absolutely must capitalize correctly; you don't have a prayer of advancing even to the first step of balancing equations if you don't. Copper (copper) is completely different than carbon-uranium (CU) for example.

Your terminology isn't quite correct -- a water molecule has one atom of oxygen whereas a molecule of hydrogen peroxide has two atoms of oxygen. What happens with peroxide is that it decomposes: 2H₂O₂ => 2H₂0 + O2^. The nascent oxygen is a strong oxidizing agent. Now, the question is whether putting an iron nail into this strong oxidizing agent will cause it to rust faster, or protect it in some way such as to slow down the rusting, or do neither. And it's time for you to determine that through an experiment.

Another idea might be to use thread to suspend a nail just above the solution surface, and see if the air above the peroxide is more corrosive than the air above plain water because of the extra oxygen content. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003

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I would like to accelerate the rusting (oxidizing) process on railroad spikes that have been welded together, the rusting process should also rust the welds. Rich Apking - Winslow, Nebraska 2004 I am also trying to corrode iron as quickly as possible to achieve an "old" look, have tried dinner salt, hydrochloric acid and electrolysis (not together!) any other thoughts ? Alan Alan mustarde - ponte de lima Portugal August 12, 2008 I have used a solution of water + table salt + white or cider vinegar [in bulk on eBay or Amazon]...sprayed on and allowed to sit in the sun. The resulting rust is darker and has a luster that is not there with just water. Ross Rucker - Katy, Texas February 12, 2009

A. My daughter and I actually conducted this experiment using faucet water which turned the water orangey and totally rusted the nail. The acetone slowly began to rust the nail, but there was no change in the liquid color. The hydrogen peroxide began to slowly change any part of the nail exposed to the air but, there was no change in the liquid's color. The milk, vinegar, and orange juice did not cause any rusting of the nail.
The water began to rust the hydrogen peroxide took over four days. The others had no effect on the nail.

I hope this helps.:)

Alexa N. [last name deleted for privacy by Editor]
- Bronx, New York
March 7, 2010

Q. Hello,

My 6th grade daughter is doing an experiment on which liquids will rust a nail faster. We are having difficulty explaining why water rusts a nail faster than hydrogen peroxide. Is it because the of the extra oxygen atom takes longer to break down, and delays the oxidization process?

Thanks for any help you can offer

Kerry S. [last name deleted for privacy by Editor]
Mother to a science fair student - Indianapolis, Indiana, United States
March 16, 2010

Q. We were wondering if hydrogen peroxide would rust iron/steel faster and found this site. Not a clear answer here yet. I would suggest another factor though. I bet pure, distilled water won't cause near as much rust as water with a little salt in it. Need to put salt in the H2O2 also. And change all the liquids daily so you are sure it is always the same. Finally you need to clean the nail with strong detergent and maybe sandpaper before the experiment begins.

I think this would be a great science fair project.

Gordon M. [last name deleted for privacy by Editor]
- Chicago, Illinois
February 15, 2011