Question

When enthalpy is positive and entropy is negative :

• A. free energy is always negative
• B. $\Delta G$ is negative, at high temperature
• C. $\Delta G$ is negative, at lower temperature
• D. free energy is never negative

Answer 1

The correct option is D free energy is never negative

When enthalpy is positive and entropy is negative, free energy change, $\Delta G$ is never negative.
$\Delta G=\Delta H-T\Delta S=+ve-T\times -ve=+ve++ve=+ve$
Positive free energy change corresponds to non spontaneous reaction.