When the heat of a reaction at constant pressure is - 25 × 10 ^ - 3...

Heat at constant pressure means enthalpy. i.e., $\Delta G = \Delta H - T \Delta S$

$\Delta H = 2. 5 \times {10}^{3}cal$

$\Delta S = 7. 4{caldeg}^{- 1}$

$T = 298K$

$\Delta G = \Delta H - T \Delta S$

$= - 25 \times {10}^{3} - 298 \times 7. 4$

$= - 4705. 2cal$

As the value of& ΔG& is& −4705.2& cal, which is a negative value, so this reaction will be spontaneous.&

Hence, the process is spontaneous.