🔋 Nernst Equation Calculator
Find a cell’s actual potential from the standard potential, electrons transferred and reaction quotient — the Nernst equation at 25 °C.
Cell potential E
1.1592 V
Nernst equation at 25 °C: E = E° − (0.0592/n)·log₁₀(Q). n = electrons transferred, Q = reaction quotient. 🔒 Computed in your browser.
How the nernst equation calculator works
At 25 °C the Nernst equation is E = E° − (0.0592/n)·log₁₀(Q), where E° is the standard cell potential, n the number of electrons transferred, and Q the reaction quotient. Enter any three of E, E°, n, Q and the tool solves for the fourth.
Uses the 25 °C convention (0.0592 = 2.303RT/F at 298 K). As Q changes, the potential shifts away from E°; at equilibrium Q = K and E = 0 (a dead battery).
Frequently asked questions
What is the Nernst equation?
E = E° − (RT/nF)·ln Q, which at 25 °C simplifies to E = E° − (0.0592/n)·log₁₀ Q. It gives a cell’s potential under non-standard concentrations.
How do I calculate cell potential with concentrations?
Compute the reaction quotient Q from the concentrations, then apply E = E° − (0.0592/n)·log Q. Enter E°, n and Q and the tool returns E.
What is n in the Nernst equation?
The number of moles of electrons transferred in the balanced redox reaction. For Cu²⁺ + Zn → Cu + Zn²⁺, n = 2.
Why 0.0592?
It is 2.303·RT/F evaluated at 298 K (25 °C): 2.303 × 8.314 × 298 / 96485 ≈ 0.0592 V. At other temperatures the coefficient changes.
What happens at equilibrium?
Q equals the equilibrium constant K and E = 0 — the cell can do no more work (it’s discharged).