Science Buddies: "Ask an Expert"

Hi,
I want to do this topic for my science project, and we are only allowed to have one independent variable. How many independent variables are there in this project? I believe there are two: the types of metals used and the environments they are put in but we are only allowed one so I am a bit confused.

Hello ET,
You are correct that type of metal and type of environment would each be an independent variable. But, all is not lost!
You could select a single environment, and then test several different metals. That would let you see how the corrosion varies by metal, for the specific environment that you use for your experiments.

Let us know if this helps, and be sure to let us know if you have more questions.