Which of the following conditions will result in a reaction that is spontaneous only at high temperatures? negative enthalpy change and negative entropy change

Question

Which of the following conditions will result in a reaction that is spontaneous only at high temperatures?
negative enthalpy change and negative entropy change
negative enthalpy change and positive entropy change
positive enthalpy change and negative entropy change
positive enthalpy change and positive entropy change

Answer 1

To say that a reaction is spontaneous means that its ΔG is negative. According to the Free Gibs energy equation, ΔG= ΔH-TΔS. From a mathematical point of view, we can see that in order to make ΔG negative, the value of ΔS (entropy) needs to be high or the value of ΔH (enthalpy) needs to be low. so the answers must be the second one because having a negative ΔH and positive ΔS means that the ΔG comes out negative.