For the voltaic cell represented by the cell \(3Cu + 2Au^{3+} \rightarrow 3Cu^{2+} + 2Au\). The value of n to be used in the Nernst equation is

6

The correct answer is (4) 6.

The Nernst equation is used to calculate the cell potential of a voltaic cell. The equation is:

\(E= E^0 - \frac{0.0591}{n} log \frac{[Oxidant]}{[Reductant]}\)

where:

E is the cell potential at a given temperature and concentration

E° is the standard cell potential

n is the number of electrons transferred in the overall reaction

0.0591 is the Nernst factor

[Oxidant] is the concentration of the oxidized species

[Reductant] is the concentration of the reduced species

In the voltaic cell represented by the cell \(3Cu + 2Au^{3+} \rightarrow 3Cu^{2+} + 2Au\), there are a total of 6 electrons transferred in the overall reaction. This is because 3 Cu atoms are oxidized to 3 Cu²⁺ ions, and 2 Au³⁺ ions are reduced to 2 Au atoms.

Therefore, the value of n to be used in the Nernst equation is 6.