ΔGO’ refers to Gibbs Free energy change (J mol-1)...?

Question

ΔGO’ refers to Gibbs Free energy change (J mol-1)

1. under non-standard conditions

2. under standard conditions of 1 atmosphere and prevailing concentrations of substrate and product, each at 1M, and at any pH

3. as in B, but at pH 7.0

4. as in B, but at pH 1.0

5. None of the above.

Answer 1

The answer is 2. When Gibb's Free Energy is 0, this means the reaction is at equilibrium. It is driving neither forwards nor backwards.