📖 Theory & Concepts ▼

Electrochemical Cell

A device that converts chemical energy to electrical energy through spontaneous redox reactions.

Anode (−): Zn → Zn²⁺ + 2e⁻ (Oxidation)
Cathode (+): Cu²⁺ + 2e⁻ → Cu (Reduction)
E°cell = E°cathode − E°anode

Daniell Cell (Zn-Cu)

  • E°(Zn²⁺/Zn): −0.76 V (more reactive, anode)
  • E°(Cu²⁺/Cu): +0.34 V (less reactive, cathode)
  • E°cell: 0.34 − (−0.76) = 1.10 V
Salt Bridge:

Maintains electrical neutrality by allowing ion flow. Usually KCl or KNO₃ in agar gel.

Voltmeter
00.51.01.52.0
0.00 V
ANODE (Oxidation)
Zn
ZnSO₄ (1M)
Zn → Zn²⁺ + 2e⁻
E° = -0.76 V
e⁻ →
Salt Bridge (KCl)
CATHODE (Reduction)
Cu
CuSO₄ (1M)
Cu²⁺ + 2e⁻ → Cu
E° = +0.34 V

📚 Cell Notation

Zn | Zn²⁺(1M) || Cu²⁺(1M) | Cu
E°cell = E°cathode - E°anode
E°cell = 0.34 - (-0.76) = +1.10 V

Observations

Connect the circuit to begin...