In the CuBr₂ cell no gases are produced. The solution contains Cu²⁺, Br^- and H₂O. Since the visual evidence suggests copper metal and liquid bromine, it is likely that these elements have smaller oxidation and reduction potentials than water itself. A check of the SRP table confirms this.

When electricity is passed through the KI solution the indicators show that the cathode side becomes basic as a gas is produced. Since potassium ions could not be reduced to form a gas, this is probably hydrogen. As we saw before, reducing neutral water produces hydrogen gas and hydroxide ions. In any case, even if potassium could form it reacts so violently with water it is not going to be around to look at!

At the anode the starch turns dark blue/black and yellowish material appears around the electrode. This is certainly not oxygen (not even in L.A.!). Iodine reacts with starch as described and we've observed its color in aqueous solution before.