We’re being asked to identify the spontaneity of a reaction for which ΔH° is positive and ΔS° is negative.
The statements given describe the spontaneity of the reaction at different temperatures.
Recall that we can determine the spontaneity of the reaction based on the signs of ΔH and ΔS.
We can use the Punnett square shown below:
A reaction for which ΔH° is positive and ΔS° is negative, is
a. Nonspontaneous only at low temperatures
b. Spontaneous only at high temperatures
c. Nonspontaneous at all temperatures
d. Spontaneous at all temperatures
e. Cannot be determined