Science Buddies: "Ask an Expert"

Hey, for my Science fair project I added different quantities (10% and 20%) of cornstarch to my MFC. In both test cases I found great results in 10% additions but 20% did not help produce any more electricity and remained fairly similar to 10%. As well I noticed a rust looking orange substance growing in my fuel cells (with more cornstarch there seemed to be more of it). Any ideas as to what the substance is, and if it could have incubated the microbes? Why does a 20% addition of cornstarch not work better than 10%?

Interesting result--don't know why 20% cornstarch would do that. My first suspicion would be some microbial growth of fungus or bacteria, but it might be a chemical reaction. Starch will react with some chemicals. Check online.

Anything that interferes with the fuel cell bacteria will reduce the power output of the MFC. Take pictures, examine the orange stuff and describe it. Use the strongest magnifier you have, or better yet a microscope, to look at it.

Let us know what you figure out.

Sybee