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The Time It Takes to Rust With Contaminants

I am a freshman student in Macon, GA. I am doing a science project about the rate at which iron rusts with contaminants such as salt and sugar. In order to do this I have to make iron rust. I want to know how long it takes for iron to rust so I will have enough time to conduct my experiment. I would also like to know if salt and sugar has an effect on rusting. If so, why?

In order to do this I have to have clean iron. How do I clean iron?

Jasmine H [surname deleted for privacy by Editor]
student - Macon, Georgia, United Sates
2006

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The best way to clean the iron would be with pumice ⇦this on eBay or Amazon [affil links] and a bristle brush, Jasmine. This will make the iron susceptible to "flash rusting", which implies that it will get some rust almost immediately (same day).

My hypothesis is that sugar will have no effect but salt will hasten the rusting. I will conjecture that it is because of the chlorine in salt. If you want to build some evidence to support that, after you do the salt experiment (sodium chloride), you could do more experiments with chemicals that contain chlorine like calcium chloride and dilute bleach (sodium hypochlorite) ⇦ bleach/sodium hypochlorite in bulk on eBay or Amazon [affil links] .

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006

Hi, I am a high school student. I am doing a science project on iron rusting. I am comparing the rusting rate of nail in tab water and sugar water. in result, the nail in the sugar water has less rust. I am just wondering why this happened? why sugar can slow the rate of rusting?

Tim P.
student - London, Ontario, Canada
March 23, 2008

The salt is a catalyst for this reaction (it lowers the amount of energy needed for the iron to react with the oxygen, i.e., to rust).

Patrick McKenna
- Charlottetown, PEI, Canada
October 19, 2010