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Corrosion on metals

I am a year 10 student from Australia and I would like to know which metals out of aluminium, iron, copper and steel corrode the quickest. This is for a student research assignment, and it's really hard to do a hypothesis on it, so can you please help me with this?

Megan S.
student - Sydney, NSW, Australia
2005

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There is no answer as stated. It is totally dependent on the environment that they are exposed to as in marine, industrial, chemical vapor and etc. The most common HS way is to look at corrosion in different liquids. You could take it a step further than most, and put a dish of diluted muriatic acid ⇦ this on eBay or Amazon [affil links] in one closed container with identical samples of each metal around it. Then do one with just a dish of water and one with straight muriatic acid. You could carry this further and try the same with ammonia ⇦ this on eBay or Amazon [affil links] or a poly sulfide or nitric acid or fertilizer or---------. Your hypothesis is strictly what environment you are testing.

James Watts
- Navarre, Florida
2005

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First of all decide what you want to test. Perhaps it is which metal corrodes fastest in seawater, or perhaps CocaCola, or even beer. Then do the test. It may take a few days, but carefully note exactly what your experimental conditions are and what you do to the reactants (e.g., shake or stir them...?). Make a note of everything you see. Remember that iron does not rust in the same colour as aluminium. Your hypothesis could be that different metals corrode at different rates in a certain liquid. Your task is to prove it and find out which one reacts fastest etc.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2005

I am a 14 year old student that lives in Inglewood, Califonia and I am doing the same project for 450 points of my second semester grade. The only thing is I didn't use iron. I used aluminum, copper, and steel and put cut 0.3048 meters of the metal strands into 0.1524 meters then wrap them around a rod of some sort (remember to have some piece of the metal in the water) and put them into 4 cups for each distilled and salt water that say copper with distilled aluminum with distilled iron with distilled and steel with distilled {do th same with the salt water)then wait for about a week or two. Copper corroded the second fastest and had a white substance on it. It looked like the aluminum did not corrode but if it did it was very light.

Bryce A
- Inglewood, California, USA
2006