Question

You’re an engineer looking for a way to remove the surface of copper without using nitric acid, because nitric acid produces harmful gases when used as an oxidizer. Will hydrogen peroxide (H2O2) dissolve solid copper by oxidizing it to Cu2+ in acidic conditions? Balance the equation and calculate the standard potential for oxidation of copper metal to Cu2+ by hydrogen peroxide (H2O2) using balanced equations found on the electrochemical series, to determine whether it will occur.

Answer 1

Balanced reduction half reaction : H₂O₂ + 2 H⁺ + 2 e^-$\rightarrow$ 2 H₂O : E^o = 1.776 V

Balanced oxidation half reaction : Cu (s) $\rightarrow$ Cu²⁺ + 2 e^- : -0.34 V

Overall reaction : H₂O₂ + 2 H⁺ + Cu (s) $\rightarrow$ Cu²⁺ + 2 H₂O

Standard potential = (1.776 V) + (-0.34 V)

Standard potential = 1.436 V

Since standard potential is positive, therefore, overall reaction will occur and hydrogen peroxide can dissolve solid copper.