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Nernst Equation Calculator.

Calculate cell potential from standard potential, reaction quotient, electron count, and temperature.

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Cell potential: 1.1 V

Cell potential

1.100000V

Educational arithmetic only. Keep units consistent and use measured or explicitly supplied chemistry inputs; this tool does not infer reaction pathways, property tables, or safety guidance.

Use Cases

Predicting cell voltage under non-standard conditions

Use this calculator to determine the actual voltage of an electrochemical cell when concentrations or pressures differ from standard conditions.

Example: Calculate the potential of a zinc-copper cell with Q=0.5 at 298 K.

Educational exercises in electrochemistry

Students can verify their manual Nernst equation calculations and explore how changes in temperature or reaction quotient affect cell potential.

Example: Check the effect of doubling Q on the cell potential.

Frequently Asked Questions

What is the Nernst equation used for?
It calculates the cell potential of an electrochemical cell under non-standard conditions, based on the standard potential, reaction quotient, number of electrons transferred, and temperature.
What units are required for temperature?
Temperature must be entered in Kelvin (K). If you have Celsius, convert to Kelvin by adding 273.15.
How does the reaction quotient affect cell potential?
The reaction quotient (Q) reflects the ratio of product activities to reactant activities. As Q increases, the cell potential decreases (for a spontaneous reaction), and vice versa.

Tips & Common Mistakes

Tips

  • Ensure the reaction quotient is dimensionless and correctly calculated from the balanced chemical equation.
  • Use the number of electrons transferred (e−) as the stoichiometric coefficient of electrons in the half-reactions.
  • Temperature must be in Kelvin; convert from Celsius by adding 273.15.
  • Standard potential is typically given at 298 K, but you can adjust temperature to see its effect.

Common Mistakes to Avoid

  • Forgetting to convert temperature from Celsius to Kelvin.
  • Using the wrong number of electrons transferred, which directly affects the logarithmic term.
  • Entering the reaction quotient as a concentration without considering activity coefficients or units.

Last updated: August 13, 2026