If an endothermic reaction occurs spontaneously at constant temperature and pressure, then which of the following is true?

Options

A. `Delta G gt 0`
B. `Delta H lt 0`
C. `Delta S gt 0`
D. `Delta S lt 0`

Answer

C

Explanation

The thermodynamic quantity of the system, the decrease in whose value during a process is equal to useful work done by the system, i, e., `Delta G= Delta H- T Delta S`, where H = enthalpy, S= entropy and T= absolute temperature. If an endothermic reaction occurs spontaneously i.e. `DeltaH` = +ve then for reaction to be spontaneous `DeltaG` should be negative that is only possible when `Delta S gt 0` at constant temperature and pressure.