Question

A reaction occurs spontaneously when

• A. $\Delta$G is$+ve$
• B. $\Delta$ H is -ve and $\Delta$ S is $+ve$
• C. $\Delta$H is +ve and $\Delta$ S is $-ve$
• D. Both $\Delta$ H, $\Delta$ S are $+ve$ and $\Delta$ H > T$\Delta$ S

Answer 1

Answer: (B)

$\Delta$ H is -ve and $\Delta$ S is $+ve$

$\Delta G=\Delta H-T\Delta S$
A reaction is spontaneous at all temperatures If $\Delta H$ is - ve and $\Delta S$ + ve.
Because in this condition $\Delta G$ will be negative