Problems obtaining ferric oxide

[Matt16]

I am making ferric oxide (Fe2O3) for a school project. I have immersed a piece of iron in a solution of tap water and salt (to allow for electrical conductivity). The piece of iron in attached to the positive terminal of a battery charger and the negative wire is attached to a section of graphite from a pencil. When i plug in the charger, the negative wire starts bubbling and after a while, a blueish-green substance begins to form at the bottom of the container and on the piece of iron.

What is this substance bluish-green? How do i correct my procedure to obtain rust?

[mathman]

What color is FeO? This is a pure guess on my part, but could you be making that?

[Manchot]

My guess is that it's an oxide of copper. The wire you're using is most-likely an alloy of it, and it is participating in the reaction.

[Gokul43201]

There are other ways to make rust. Check out this thread : http://www.physicsforums.com/showthread.php?t=32161&highlight=rust

[chem_tr]

Hello, the bluish-green substance is more likely to be a copper compound rather than iron. The how and why of it is uncertain for now, it may involve electrochemical oxidation order.