3 out of 5
If the change in free energy of a reaction is zero at constant temperature and pressure, what is true regarding such a system?
|A||The reaction is spontaneous|
|B||The reaction is nonspontaneous|
|C||The reaction is at its equilibrium state|
|D||Cannot be predicted|
Ans. C The change in free energy (ΔG) is related to enthalpy and entropy by the following equation:
ΔG = ΔH – T ΔS
In this question, the change in free energy is zero. This means that there is no net transfer of free energy. This in turn means that the forward and backward reactions are both favorable and thus the reacting system is in equilibrium.