Question

Why do activity coefficients not appear in the charge andmass balance equations?

Short answer

Activity coefficients do not appear in the mass and charge balance of equations because charge and mass are proportional to molarity, not activity coefficients.

Step-by-step solution

Definition of activity coefficients

The activity coefficient \(\gamma \)measures the deviation of behavior from ideality,rapidly decreases as ionic strength increases.

Role of Activity coefficients in charge and mass balance equations

Charge and mass are proportional to molarity, not activity.

And also, activity co-efficient does not have any role in charge and mass transfer balance equations.

The only one step in which activity coefficients appear is in, writing the equilibrium constant expression for each chemical reaction.

Therefore, Since the charge and mass of the atoms are conserved in the reaction,

activity coefficients do not appear in the mass and charge balance of equations.