What do you understand by standard e.m.f. of a cell ? Derive a relationship between standard emf of a cell and equilibrium constant.

Explanation

### Step-by-Step Solution

**Step 1: Understanding Standard EMF of a Cell**
The standard electromotive force (emf) of a cell is defined as the potential difference between the two electrodes of an electrochemical cell when no current is flowing. It is a measure of the cell's ability to drive an electrochemical reaction under standard conditions (1 M concentration for solutions, 1 atm pressure for gases, and a temperature of 25°C).

**Step 2: Standard Reduction Potentials**
The standard emf (E°) of a cell can be calculated using the standard reduction potentials of the cathode (E°_cathode) and anode (E°_anode). The relationship is given by:
\[
...