Explanation:

Chemical Potential:
Chemical potential is a thermodynamic concept that represents the potential energy of a substance due to its concentration. It is defined as the change in Gibbs free energy (G) with respect to the number of moles (n) of a component in a system at constant temperature and pressure.

The given options:
a) chemical potential = n/G
b) chemical potential = 1/(G*n)
c) chemical potential = G*n
d) chemical potential = G/n

Correct answer: Option D

Explanation:
The chemical potential is defined as the change in Gibbs free energy (G) with respect to the number of moles (n) of a component in a system at constant temperature and pressure.

The correct formula for the chemical potential in this case is given by option D: chemical potential = G/n.

Understanding the formula:
1. The chemical potential is inversely proportional to the number of moles (n).
2. As the number of moles decreases, the chemical potential increases.
3. This implies that the chemical potential is higher when there is a higher concentration of the component in the system.
4. The chemical potential is directly related to the Gibbs free energy (G) of the system.
5. The higher the Gibbs free energy, the higher the chemical potential.
6. Conversely, the lower the Gibbs free energy, the lower the chemical potential.
7. Therefore, the chemical potential is directly proportional to the Gibbs free energy.
8. The chemical potential is not affected by any other factors such as the total volume or the size of the system.

Conclusion:
The correct formula for the chemical potential in a phase with only one constituent is given by option D: chemical potential = G/n. This formula represents the relationship between the Gibbs free energy (G) and the number of moles (n) of the component in the system. The chemical potential is directly proportional to the Gibbs free energy and inversely proportional to the number of moles.