I started talking to one student about a Science Fair project using the conductivity of water as a proxy for water contamination. As a demonstration, a solution of baking soda is used. Not only does the solution conduct electricity, but gas bubbles are emitted, which supposedly shows the electrolysis of water into its constituent hydrogen and oxygen.
Except I don't think I believe it. Instead, I think the bubbles might be carbon dioxide from the more acidic solution around the cathode.
Yet, this electrolysis experiment is a common educational high-school science experiment with a big literature. And I disagree with it.
I didn't think this high-school student knew very much. Diffident and unsure of herself. I hurried off.