| Reactions of Copper |
Reactions with air |
| Copper metal is stable in air under normal conditions. When red hot, copper metal and oxygen react to form Cu2O. |
4Cu(s) + O2(g) 2Cu2O(s) |
Reactions with halogens |
| Copper reacts with fluorine, chlorine and bromine to form copper(II) dihalides. |
Cu(s) + F2(g) CuF2(s) |
Cu(s) + Cl2(g) CuCl2(s) |
Cu(s) + Br2(g) CuBr2(s) |
Reactions with acids |
| Copper metal dissolves in hot concentrated sulphuric acid to form solutions containing the aquated Cu(II) ion together with hydrogen gas. |
Cu(s) + H2SO4(aq) SO42-(aq) + H2(g) |
| Copper metal also dissolves in dilute or concentrated nitric acid. |
| Reduction Potentials | |
| Balanced half-reaction | E0 / V |
Cu2+ + 2e- Cu(s) |
+0.337 |
Cu2+ + e- Cu+ |
+0.153 |
Cu+ + e- Cu(s) |
+0.521 |
HCuO2- + 3H+ + e- Cu+ + 2H2O
|
+1.73 |
CuO22- + 4H+ + e- Cu+ + 2H2O
|
+2.51 |
HCuO2- + 3H+ + 2e- Cu(s) + 2H2O
|
+1.13 |
CuO22- + 4H+ + 2e- Cu(s) + 2H2O
|
+1.52 |
2Cu2+ + H2O + 2e- Cu2O(s) + 2H+ |
+0.20 |
2HCuO2- + 4H+ + 2e- Cu2O(s) + 3H2O
|
+1.78 |
2CuO22- + 6H+ + 2e- Cu2O(s) + 3H2O
|
+2.56 |
CuO + 2H+ + e- Cu+ + H2O
|
+0.62 |
Cu2+ + Br- + e- CuBr(s) |
+0.64 |
Cu2+ + Cl- + e- CuCl(s) |
+0.54 |
Cu2+ + I- + e- CuI(s) |
+0.86 |
CuI(s) + e- Cu(s) + I- |
-0.185 |
Cu(NH3)42+ + e- Cu(NH3)2+ + 2NH3 |
-0.01 |
Cu(NH3)2+ + e- Cu(s) + 2NH3 |
-0.12 |
Cu(NH3)42+ + 2e- Cu(s) + 4NH3 |
-0.07 |