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My metals won't rust

Dear Sir,

I am in the 4th grade. For my science project I am trying to see which metal rusts fastest but the nails are not rusting at all. I put stainless steel, zinc and brass in tap water but they are not rusting. Can you tell me which is supposed to rust faster and why it is not? I did learn that iron and oxygen cause rust but not for me.

Thank you,

Karin
- West Palm Beach, Florida
2003

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First of two simultaneous responses --

I am not surprised! You have chosen every type of nail that is designed to prevent rusting! Stainless steel will take a very long time to rust as the metal is made to resist the effects of corrosion. Zinc is put onto steel nails to give it a protective coating and brass nails don't have any iron in them, unless they are the cheap electroplated type. If the brass nails are the cheap ones, they are made from iron or steel and are plated with a brass coating that protects the steel. By the way, brass is a mixture of copper and zinc. I suggest you take the zinc nails and rub off all the zinc and then repeat the test. Similarly, try to rub of the brass from the brass nails to see if they are the upmarket or down market nails! One fun thing to do with brass is to put it into a vinegar [in bulk on eBay or Amazon] solution and see what happens. All corrosion takes some time, but have faith and do the experiments. This subject has also been well covered on this web site, so use the built-in search engine to help you.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2003

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Second of two simultaneous responses --

Karin,

As you said, rust is oxidized iron (steel). Stainless Steel has corrosion reducing elements in it and thus will not rust in any rapid fashion. Zinc will primarily dissolve at a very slow rate until it reaches an equilibrium. Brass is quite corrosion resistant, that is why you find so much brass on old boats. If you want rust, you will need to strip the zinc coating off of regular nails or better yet, buy some "cut" nails that are flat like antique nails. You will have to sand these to a very bright white metal surface. Clean with a soapy hot water solution and rinse well. These will rust in a matter of hours to days, depending on what else is in the water. Your brass and zinc will never rust because of no iron. They may corrode slightly, but that is not "rust".

James Watts
- Navarre, Florida
2003

Well it will depend on what kind of nails you used? You can tell that there are thousands of nails? But some are coated but if you read the package before you get they get the nails you should get the non - coated nails because that is what my family siad and what my teacher told me well I'm in the 6th grade? So I'm doing this as a science fair too but my dad is supplying the things he knows a lot of this because he has his own shoppe so he know a lot well hey when I get more info I will get it to you enjoy and remember follow these tips ?

Katie S.
- Hubbard, Ohio, U.S.A
2004

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Hi,

Yes they are right it depends on the nails. I was doing the same thing except I put Zinc roofing nail nails in: 140 ml water 140 ml water 10 drops vinegar, 140 ml water 1 ml salt none rusted but the one in vinegar started to grow algae. I also used a regular steal nail that went beserk so now you have one type of nail that will work. Have fun with the project.

Melissa T.
- Oregon
2004

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Hi

You should do what all these people say, but also use your own brain power, thats the most important thing also DO YOUR BEST thats all anyone can do! Good luck and just go for it girl!

Toby N.
- Liverpool, Merseyside, England
2004

Which will rust faster steel, brass, copper or zinc.

Lilly S
- Maryland
March 24, 2012

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Hi, Lilly.

Only steel (iron) can rust because "rust" is a compound of iron and oxygen, and there is no way to get it from brass, copper, or zinc. However, almost anything can corrode to some extent, so yes, how much those four metals corrode sounds like a good thing for you to try to find out from your experiment.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
March 25, 2012