Which of the following statements is/are correct?

Options

A. For spontaneous process, `Delta`G must be negative
B. At equilibrium, `Delta`G = 0
C. At equilibrium, `Delta G^(@) = 0`
D. AT equilibrium, `Delta G^(@) = -2.303 RT log K_(P)`

Answer

To determine which of the statements related to Gibbs free energy (ΔG) are correct, we will analyze each statement step by step.

### Step 1: Analyze the first statement
**Statement:** For a spontaneous process, ΔG must be negative.

**Explanation:** This statement is correct. A spontaneous process is one that occurs without needing to be driven by an external force. According to thermodynamics, if the change in Gibbs free energy (ΔG) is negative, the process can occur spontaneously.

### Step 2: Analyze the second statement
**Statement:** At equilibrium, ΔG is equal to 0.

**Explanation:** This statement is also correct. At equilibrium, the forward and reverse reactions occur at the same rate, and there is no net change in the concentrations of reactants and products. At this point, the Gibbs free energy change (ΔG) for the system is zero, indicating that the system is at its lowest energy state under the given conditions.

### Step 3: Analyze the third statement
**Statement:** At equilibrium, ΔG° is equal to 0.

**Explanation:** This statement is incorrect. ΔG° (standard Gibbs free energy change) is a constant value that represents the change in Gibbs free energy under standard conditions (1 bar pressure, 1 M concentration, etc.). It does not equal zero at equilibrium; rather, at equilibrium, ΔG is zero, not ΔG°.

### Step 4: Analyze the fourth statement
**Statement:** At equilibrium, ΔG° is equal to -2.303 RT log Kp.

**Explanation:** This statement is correct. The relationship between the standard Gibbs free energy change (ΔG°) and the equilibrium constant (Kp) is given by the equation ΔG° = -RT ln Kp. When converted to base 10 logarithm, it becomes ΔG° = -2.303 RT log Kp. This equation shows how the standard Gibbs free energy change is related to the position of equilibrium.

### Conclusion
Based on the analysis:
- The first statement is correct.
- The second statement is correct.
- The third statement is incorrect.
- The fourth statement is correct.

### Final Answer
The correct statements are the first, second, and fourth.

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