Question

question 4
if the δg of the reaction that changes diamonds to graphite is -693 kcal/mol, then the reaction is
a spontaneous and endergonic
b spontaneous and exergonic
c not spontaneous and exergonic
d not spontaneous and endergonic

Explanation:

The sign of $\Delta G$ determines reaction spontaneity. A negative $\Delta G$ indicates a spontaneous reaction. Exergonic reactions release energy ($\Delta G < 0$) and endergonic reactions absorb energy ($\Delta G>0$). Since $\Delta G=- 693$ kcal/mol (negative), the reaction is spontaneous and exergonic.

Answer:

B. spontaneous and exergonic