Calculate The Cell Potential of The Following

Determine the cell potential of electrochemical cells using the Nernst equation. This calculator helps you calculate the voltage of a cell based on standard reduction potentials and concentrations of reactants and products.

How to Use This Calculator

To calculate the cell potential:

Enter the standard reduction potential (E°) for the cathode reaction in volts.
Enter the standard reduction potential (E°) for the anode reaction in volts.
Enter the concentration of the cathode species in molarity (M).
Enter the concentration of the anode species in molarity (M).
Click "Calculate" to see the cell potential.

The calculator will display the cell potential in volts and show a graph of how the potential changes with concentration.

Nernst Equation Formula

The Nernst equation calculates the cell potential (E) of an electrochemical cell:

E = E°_cell - (RT/nF) * ln(Q)

Where:

E = Cell potential (V)
E°_cell = Standard cell potential (V)
R = Gas constant (8.314 J/mol·K)
T = Temperature in Kelvin (298 K at 25°C)
n = Number of electrons transferred
F = Faraday constant (96,485 C/mol)
Q = Reaction quotient

For a simple cell with one electron transfer (n=1), the equation simplifies to:

E = E°_cell - (0.0592/T) * log(Q)

Worked Example

Let's calculate the cell potential for a zinc-copper cell:

Cathode reaction: Cu²⁺ + 2e⁻ → Cu (E° = +0.34 V)
Anode reaction: Zn → Zn²⁺ + 2e⁻ (E° = -0.76 V)
Standard cell potential: E°_cell = 0.34 - (-0.76) = 1.10 V
Concentration of Cu²⁺: 1 M
Concentration of Zn²⁺: 1 M

Using the simplified Nernst equation:

E = 1.10 - (0.0592/298) * log(1/1) = 1.10 V

The cell potential is 1.10 volts when the concentrations are equal.

Interpreting Results

The cell potential tells you:

How much electrical work the cell can do
Whether the reaction is spontaneous (positive potential)
How the potential changes with concentration

If the potential is positive, the reaction is spontaneous and can produce electricity. If negative, the reaction is non-spontaneous.

Note: This calculator assumes ideal conditions and doesn't account for temperature effects beyond the standard 25°C.

Frequently Asked Questions

What is the difference between standard cell potential and cell potential?

Standard cell potential (E°) is measured under standard conditions (1 M concentrations, 25°C). Actual cell potential (E) depends on concentrations and temperature.

How does concentration affect cell potential?

Increasing the concentration of products or decreasing reactants increases the cell potential, making the reaction more spontaneous.

Can I use this calculator for multi-electron reactions?

Yes, but you'll need to adjust the Faraday constant (F) in the calculation by multiplying by the number of electrons transferred.

What if my reaction doesn't fit the standard format?

For complex reactions, you may need to break them down into half-reactions and calculate each half-cell potential separately.