Answer:
Cu(s) + 2AgNO₃(aq) → 2Ag(s) + Cu(NO₃)₂ (aq)
Explanation:
Reactants: Cu(s), AgNO₃(aq)
This is a redox reaction, where the Ag and the Cu change the oxidation state
Ag, from +1 to 0 → reduction
Cu, from 0 to +2 → oxidation
Ag⁺ + 1e⁻ → Ag Reduction gains an electron
Cu → Cu²⁺ + 2e⁻ Oxidation releases 2 electrons
We multiply the half reactions:
(Ag⁺ + 1e⁻ → Ag) . 2 = 2Ag⁺ + 2e⁻ → 2Ag
(Cu → Cu²⁺ + 2e⁻) . 1 = Cu → Cu²⁺ + 2e⁻
We sum both reaction, so we cancel the e⁻:
2Ag⁺ + 2e⁻ + Cu → 2Ag + Cu²⁺ + 2e⁻
We add the other ions, to get the balanced equation:
Cu(s) + 2AgNO₃(aq) → 2Ag(s) + Cu(NO₃)₂ (aq)
