In an endothermic reaction, if there is a loss in entropy the reaction will

Correct answer: Not be spontaneous

Explanation: Spontaneity is judged by Gibbs free energy: \( \Delta G = \Delta H - T\Delta S \). For an endothermic reaction, \( \Delta H > 0 \); a loss in entropy means \( \Delta S < 0 \). Then

\( \Delta G = (+) - T(-) = (+) + (+) \Rightarrow \Delta G > 0 \) at all temperatures, so the reaction is not spontaneous.

• Be indeterminate — Incorrect. The signs make \( \Delta G \) definitely positive.
• Be spontaneous — Incorrect. \( \Delta G \gt 0 \).
• Not be spontaneous — Correct.
• Be at equilibrium — Incorrect. Equilibrium requires \( \Delta G = 0 \), which cannot occur here for any positive temperature.