Statement I: The potential difference between the two electrodes of galvanic cell is called the cell potential

Statement II: Cell potential is equal to the emf of a cell

Statement I is correct but Statement II is false

Statement I: The potential difference between the two electrodes of a galvanic cell is called the cell potential.
Statement II: Cell potential is equal to the emf of a cell.
The correct answer is:
3. Statement I is correct, but Statement II is false.
Statement I is correct. The potential difference between the two electrodes (anode and cathode) of a galvanic cell is indeed called the cell potential. It represents the electrical energy difference per unit charge between the two electrodes and drives the flow of electrons through the external circuit.
However, Statement II is false. The cell potential and electromotive force (emf) of a cell are related but not the same thing. The cell potential (\(E_{\text{cell}}\)) is the actual potential difference measured between the two electrodes of the cell when it is operating and current is flowing. It depends on the specific reaction occurring in the cell and is measured experimentally.

On the other hand, the electromotive force (emf) of a cell is the maximum potential difference that a cell can have when no current is flowing through it. It is the potential difference that would exist across the electrodes if the cell had zero internal resistance. The emf is a theoretical concept and cannot be measured directly. It is related to the cell potential and the internal resistance of the cell through the equation:

\[\text{emf} = E_{\text{cell}} + (I \times r)\]

Where:
\(\text{emf}\) = electromotive force (maximum potential difference) of the cell
\(E_{\text{cell}}\) = cell potential (measured potential difference)
\(I\) = current flowing through the cell
\(r\) = internal resistance of the cell

In summary, Statement I is correct, but Statement II is false because cell potential and emf are related concepts but not equal. The correct answer is 3.