Question

What is the formula to calculate rate of oxidation or rate of reduction during equilibrium?

(a) r0=rR=i0nF

(b) r0=rR=i0/nF

(c) r0=rR=i0n/F

(d) r0=rR=nF/i0

This question was posed to me in a national level competition.

Question is taken from Modern Theory Principles topic in chapter Modern Theory Principles of Corrosion Engineering

Answer 1

Correct answer is (b) r0=rR=i0/nF

The best I can explain: Equilibrium is defined as the state at which rate of oxidation is equal to the rate of reduction. And the formula to calculate rate of oxidation or reduction is r0=rR=i0/nF where i0 is exchange current density, n is number of electrons involved and F is faraday’s constant.