Which of the following statement is incorrect?

To determine which statement is incorrect, we need to analyze the thermodynamic criteria for spontaneity, equilibrium, and non-spontaneity using Gibbs free energy change ($\Delta G$).

Gibbs free energy change ($\Delta G$) is the thermodynamic potential used to calculate the maximum reversible work that may be performed by a thermodynamic system at a constant temperature and pressure. The criteria are as follows:

1. For a reversible (equilibrium) process:
The system is in a state of balance, meaning no net work can be extracted, and the free energy is at a minimum. Therefore,
$\Delta G=0$.
Thus, the statement "∆G = 0 for reversible process" is correct.

2. For a spontaneous process:
A spontaneous process occurs naturally without external intervention and leads to a decrease in the system's free energy. Therefore,
$\Delta G<0$ (negative value).
Thus, the statement "∆G < 0 for spontaneous process" is correct.

3. For a non-spontaneous process:
A non-spontaneous process requires an input of energy from an external source to proceed, leading to an increase in the system's free energy. Therefore,
$\Delta G>0$ (positive value).
Thus, the statement "∆G > 0 for non-spontaneous process" is correct.

Comparing these criteria with the options, we see that the statement "∆G > 0 for spontaneous process" contradicts the condition for spontaneity ($\Delta G<0$). Hence, it is incorrect.