Hey there PF, I'm trying to determine the reaction equation for a little home experiment I've been conducting. The setup is very minimal: copper metal in a solution of 3% H2O2 and 5% CH3COOH. In reality, I'm probably missing something fairly straightforward. The reaction occurs very slowly, but within a few minutes it becomes very clear that this is a redox reaction, seeing as solid copper is dissolving into solution. As such, the overall reaction can generally be determined by examining the half-reactions. The first of these half-reactions is very obvious: Cu(s) → Cu2+(aq) + 2e- (It forms the cupric ion because the product is copper acetate, Cu(CH3COO)2). The second reaction, however, is slightly more annoying because H2O2 can form a few different combinations of products. Seeing as it is the only available oxidizing agent, I assumed the equation was something like this: H2O2(aq) + 2e- + 2H+(aq) → 2H2O(l) (Hydrogen ions are donated by CH3COOH, and as they are consumed, copper (II) ions are formed, thus the net charge of the solution remains 0) Thus, by adding these two equations together, I assumed the overall equation to be Cu + H2O2 + 2CH3COOH → Cu(CH3COO)2 + 2H2O. All seemed fine, until I looked at the solution again, and realized that gas was being evolved (oxygen, not hydrogen, as determined by re-ignition of a splint). My first guess was perhaps that the freshly-etched copper was acting as a catalyst for the decomposition of hydrogen peroxide. However, after removing a piece from the solution, rinsing it quickly, and placing it in a solution of just hydrogen peroxide, I wasn't able to notice any gas being evolved. Does anyone know the actual equation, or have suggestions for possible side reactions occurring?