h202

[Danberman]

so i was thinking, if h20 generates 2 hydrogen + 1 oxy, h202 should make 2 h 2 o. So i tried it by mixing some salt with 3% hydrogen peroxide, placed some aluminum foil for electrodes, and connected it to 24v. It produced tons of gas and got fairly hot, but the strange thing was the reaction didnt stop when i disconnected the power. I could still hear and see bubbles coming off the foil. Can someone explain in terms understood by someone who has not yet taken highschool chem what is happening?

[kumaran]

Hi Danberman,

I do not know the reaction with salt + hydrogen peroxide + aluminium. One thing for sure is 24V is very high for two aluminum foil. Aluminium foil will corrode faster.

If you have access to LYE, just mix some amount with normal water. Drop small piece of aluminium into the solution. Check out the reaction.

The reaction produces H2 gas and heat. Also consumes aluminium in about 20 to 30 minutes. This simple experiment doesn't need any input power.

[BEMET]

In part your reaction is creating some hydrochloric acid (HCl) while voltage is being applied to the electrodes and only one electrode is dissolving into solution. When the current is removed the HCl reacts with both of the Al electrodes in the dilute HCl.