The total EMF of a voltaic cell is greater than zero. Which of the following statements is true?

\(\Delta G < 0\) and \(E_{cell}\) is intensive property

The correct answer is option 3. \(\Delta G < 0\) and \(E_{cell}\) is intensive property.

The total electromotive force (EMF) of a voltaic cell, \(E_{\text{cell}}\), is the measure of the cell's ability to generate electrical energy from a chemical reaction.

Given that the total EMF of the voltaic cell is greater than zero, it implies that the cell is capable of driving a spontaneous chemical reaction and producing electrical energy.

Now, let's analyze the statements:

1. \( \Delta G = 0 \) and \(E_{\text{cell}}\) is an extensive property.

If \( \Delta G = 0 \), it indicates that the reaction is at equilibrium, not spontaneous. This contradicts the premise that the cell is capable of driving a spontaneous reaction. Additionally, \(E_{\text{cell}}\) is an intensive property, not extensive.

2. \( \Delta G > 0 \) and \(E_{\text{cell}}\) is an intensive property.

If \( \Delta G > 0 \), it implies that the reaction is non-spontaneous, which contradicts the premise. Additionally, \(E_{\text{cell}}\) is indeed an intensive property.

3. \( \Delta G < 0 \) and \(E_{\text{cell}}\) is an intensive property.

This statement aligns with the premise. If \( \Delta G < 0 \), it indicates that the reaction is spontaneous. And \(E_{\text{cell}}\) is indeed an intensive property.

4. \( \Delta G < 0 \) and \(E_{\text{cell}}\) is an extensive property.

If \(E_{\text{cell}}\) were an extensive property, it would depend on the size of the system, which is not the case. Additionally, \( \Delta G < 0 \) aligns with the premise.

Based on the analysis, the correct statement is (3) \( \Delta G < 0 \) and \(E_{\text{cell}}\) is an intensive property.