Enter the molar mass, amperes, time, and oxidation state into the calculator to determine the current efficiency.

Current Efficiency Formula

The following equation is used to calculate the Current Efficiency.

Ec = (M*I*T) / (N*F)
  • Where Ec is the current efficiency
  • M is the molar mass (weight of displaced element) (grams)
  • I is the current in amperes
  • T is the time in seconds
  • N is the Number of displaceable electrons per atom (oxidation state)
  • F is Faraday’s Constant (96487 Coulombs)

To calculate the electrical current efficiency, divide the product of the molar mass, current, and time by the product of the number of displaceable electrons per atom and the Faraday constant.

What is a Current Efficiency?


Current efficiency measures the ratio of electrochemical equivalent current density for a reaction relative to the total applied current density.

How to Calculate Current Efficiency?

Example Problem:

The following example outlines the steps and information needed to calculate Current Efficiency.

First, determine the molar mass of the displaced element. In this example, the molar mass is 150 grams.

Next, determine the current. For this problem, the current is measured as 10 amperes.

Next, determine the total time in seconds. In this case, the total time of the reaction is 200 seconds.

Next, determine the oxidation state. This is provided as 2.

Finally, calculate the current efficiency using the formula above:

Ec = (M*I*T) / (N*F)

Ec = (150*10*200) / (2*96487)

Ec = 1.5546